Fundamentals of the Human Soul

You are a spiritual entity called human and you have a soul. Your body is like the hardware, and your soul is like the software. Together, they are ultimately responsible for the actions you take, how your perceive the world, the thoughts you have, the inner reality you inhabit in imagination. It contains your rationality, intelect, emotions and even the instructions for beating your heart. This document will explain the basics you need to understand and operate it.

The modern world, unlike better times centuries ago, has a lot of confusion in its understanding of the soul. It is intentional and some people are deeply invested in causing it. This document presents the only correct and comprehensive understanding brought to you by the Roman Catholic Apostolic Church, and its philosophy genius called Saint Thomas Aquinas.

Preface: Analogies Between Software and Soul

Before heading in, it helps to borrow software analogies—not because a human is software, but because they make the structural clarity of Thomistic anthropology immediately legible to a modern mind.

What turns hardware into a running system is not another component, but an organizing architecture. This is what Aquinas calls the soul as the form of the body: the principle that makes a body this living agent rather than raw matter. Likewise, what distinguishes powered-off hardware from a live process is the principle that makes the system operate at all—the first principle of life. And just as a real product is not “just code” but code-in-runtime-with-infrastructure, the human person is neither “just soul” nor “just body,” but one body–soul composite. The way an algorithm is not reducible to any single transistor state also mirrors Aquinas’s claim that intellect and will are immaterial and subsistent: not floating ghosts, but operations whose truth is not identical with any physical configuration, even though their ordinary execution still depends on lower layers like memory, IO, and representation.

Seen this way, Aquinas’s doctrine of powers reads like a layered stack. Always-on maintenance services correspond to the vegetative powers. Sensors and perception pipelines map to the external and internal senses. Reward and aversion systems map to the appetitive powers. Actuation maps to the locomotive power. Above all sits the planner and executive: intellect as world-model and practical reason, will as commitment and choice. The central Thomistic claim is architectural: higher powers are meant to govern lower powers—the control plane constrains the data plane—so sensation and passion serve reason rather than rule it.

This framing explains why bodily order matters ascetically without collapsing into “health equals holiness.” If the platform is unstable, higher-level behavior degrades: poor sleep, bad diet, and constant stimulation mechanically impair attention and prayer, not because the soul becomes material, but because the human being is one system. Gluttony and intemperance resemble runaway processes that starve critical services like recollection and rational clarity. The internal senses clarify why imagination discipline is governance, not paranoia: imagination acts as a simulator, memory as an experience log, and the cogitative power as a learned heuristic. Flood these layers with noise, and they keep firing callbacks—images, anticipations, cravings—creating “inner latency,” where prayer feels like a cold start because the cache is full.

From this angle, the passions are not enemies but the affective state machine of the sensitive appetite. One subsystem handles attraction and repulsion (the concupiscible), another handles difficulty and threat (the irascible). Their conflicts resemble competing objectives: comfort versus duty, flight versus perseverance. Morality enters where consent enters. Signals are neutral; endorsement makes them voluntary. Antecedent passions resemble unrequested interrupts; consequent passions are deliberately harnessed energy. Virtue is hardened reliability: habits that tune the system so good action becomes easier and more stable—prudence improves the model, justice keeps the objective honest, fortitude increases resilience, and temperance rate-limits pleasure so short-term reward loops stop hijacking the system.

These analogies are scaffolding, not reductions. You are not software; you are a spiritual being whose highest operations transcend matter. Their purpose is to show that Thomistic categories describe an intelligible interior architecture—one that allows disorder to be located and corrected with precision rather than vagueness.

Introduction

In Thomistic philosophy – following Aristotle and refined by St. Thomas Aquinas – the human soul is understood as the immaterial form of the living human body, and the first principle of all vital activities. Aquinas defines the soul as “the first principle of life of those things which live”, meaning that it is the fundamental cause that makes an organism alive. In humans, this soul is rational, possessing spiritual faculties that transcend matter. Unlike a material organ, the rational soul can operate apart from the body (for example, in abstract thinking), and so Aquinas concludes that the human soul is an incorporeal and subsistent entity – capable of surviving bodily death. At the same time, the soul is not a separate “ghost” inhabiting the body; rather, it is the form that actualizes the matter of the body into one unified human being. Every capability we have – nutrition, sensation, emotion, intellect, will – flows from the soul’s intrinsic capacities or powers. Understanding these powers and their proper order is essential for self-reflection and ascetical discernment. In Thomistic thought, the well-ordered soul is one in which higher powers (reason and will) govern the lower (passions and bodily appetites) . This manual will introduce all the key concepts, divisions, and “grammar” of the Thomistic soul, providing a map of the soul’s powers and a toolkit for wisely managing one’s inner life. We will survey the nature of the soul, the hierarchy of its powers (vegetative, sensitive, and rational), the passions and their role in moral life, the virtues that perfect each faculty, and practical methods of ascetical self-governance drawn from this classical framework. The goal is to equip you with the 20% of Thomistic anthropology that yields 80% of the insight – a comprehensive yet focused resource for understanding what the soul is and how to guide it toward order, virtue, and ultimately, its highest end.

I. Essence of the Human Soul: Form and Immortal Substance

At the most basic level, the soul is what makes a living thing alive. In Aquinas’s Aristotelian definition, the soul is not a body or material thing itself, but the act of a body – the organizing principle that makes an organism what it is. Just as the principle of heat is not a physical object but a quality that makes something hot, the soul is an immaterial principle that makes the body a living, functioning being. Specifically, the human soul is the form of the human body, meaning it structures the matter of the body into a coherent, life-performing whole. Because our soul includes higher rational capacities, it differs fundamentally from the souls of plants or animals. Aquinas teaches that every living thing has a soul (in the broad sense of a life-principle), but only the human soul is rational and thus spiritual.

Spirituality and Subsistence: The rational character of the human soul means it has activities that are intrinsically independent of matter – most notably, intellect and will. Our intellect can grasp universal ideas and truths, which are not material things, and it does so without using a bodily organ (unlike seeing or hearing which require eyes or ears). Aquinas argues that “the intellectual principle which we call the mind or intellect has an operation per se apart from the body. Now only that which subsists can have an operation per se… We must conclude, therefore, that the human soul…is something incorporeal and subsistent”. In other words, because the human soul can operate independently of bodily organs (for example, when thinking of abstract concepts), it must itself be capable of existing independently of the body. This underpins the immortality of the soul: when the body dies, the soul – being subsistent and immaterial – does not dissolve, but continues to exist and to exercise intellectual and volitional activity (albeit in an incomplete state until reunited with the body). By contrast, the souls of brute animals or plants have no operations apart from matter; all their activities (sensing, growing, etc.) are tied to bodily organs, so those souls are not subsistent and perish when the organism dies. Thus, the human soul holds a unique metaphysical status: it is the spiritual form of the body, the seat of our personhood, and naturally ordered to live forever.

Body-Soul Unity: Despite its spiritual nature, the soul is not the whole person, nor an alien presence in the body. Aquinas insists that “the soul is not the man” by itself; rather, man is a composite of soul and body. The soul is the substantial form uniting with matter to constitute one being. All human operations result from this union: even thinking, while rooted in an immaterial intellect, normally relies on imagination and brain processes; conversely, even bodily actions (like speaking or walking) originate from the soul’s faculties of will and appetite. The body is truly our body because it is informed by our soul, and the soul expresses itself through the body. This holistic view avoids both reductive materialism (treating thought as merely brain activity) and Cartesian dualism (treating the soul as a complete “ghostly” person using a body as a tool). Instead, the soul and body function as one unitary substance. In Thomistic terms, the soul is the form, the body the matter, and together they compose the one essence of a human being. Consequently, care of the soul cannot ignore the body (since bodily conditions impact our soul’s operations), and care of the body should be ordered to the soul’s good. We must neither despise the bodily nor idolize it; the proper approach is an integration where the spiritual soul rightly rules the bodily aspect, elevating it without abusing it.

Powers Flowing from the Soul: The rich variety of human activities – from digesting food to abstract mathematics, from emotional delight to free choice – all spring from the single soul as their source. However, because these activities differ greatly, Aquinas (following Aristotle) speaks of the soul as having distinct powers or faculties. A soul’s powers are the various capacities it has to perform different types of acts. For example, “to see” and “to imagine” are different operations, so they proceed from different powers (sight from the visual power, imagination from the imaginative power), even though both powers belong to one soul. The powers are not parts of the soul in a spatial sense, but conceptual distinctions based on what objects they address. Aquinas famously enumerates a hierarchy of five genera of powers in the human soul (and analogous powers in other living things):

• Vegetative powers – those that deal with fundamental life-functions (shared with plants), such as growth, nutrition, and reproduction.
• Sensitive powers – those enabling perception and bodily sensation (shared with animals). These include the five external senses (sight, hearing, taste, touch, smell) and the internal sensory powers like imagination.
• Appetitive powers – the powers by which we incline toward or away from things apprehended (in animals, the drives or passions; in humans, both the sensory desires and the rational will). Aquinas often splits these into the sensitive appetite (which further divides into concupiscible and irascible passions) and the intellectual appetite (the will).
• Locomotive power – the ability to move oneself in space (walking, flying, etc., possessed by animals and humans but not plants).
• Intellectual powers – the distinctly human faculties of intellect (reason) and will, by which we know truth and choose freely according to reason.

In the following sections, we will examine each category of powers more closely, then consider how they interrelate and how to cultivate a right order among them.

II. The Hierarchy of the Soul’s Powers

1. Vegetative Life – The Soul’s Basic Vital Functions

At the foundational level are the vegetative powers, which Aquinas also calls the nutritive powers. These are the operations we share with the lowest forms of life (plants). They include: nutrition, the ability to assimilate food and convert it into the substance of the organism; growth, the power of self-development to reach a proper size or maturity; and reproduction, the power to generate new life of the same species. These activities are utterly unconscious and automatic in us – governed by the soul without any deliberation. We do not decide to digest our food or to grow taller; such processes are directed by the soul’s vegetative principles in conjunction with the body’s organs (stomach, liver, cell DNA, etc.). In Thomistic terms, the vegetative soul operates through a corporeal organ and by virtue of a corporeal quality (for example, bodily heat aids digestion). It is the lowest level of soul because its operations, while intrinsic (arising from within the organism), are entirely bound to the physical and chemical processes of the body.

For practical ascetic purposes, the vegetative functions are not the direct focus of moral training – one cannot will oneself to stop metabolizing or to grow faster. However, they underlie higher powers and set conditions for them. For instance, a malnourished or sleep-deprived person will struggle with higher tasks like concentrating or exercising patience. Thus, caring for basic bodily health (reasonable nutrition, rest, etc.) can be seen as a virtue of stewardship, ensuring the vegetative powers properly support the soul’s higher activities rather than hinder them. Gluttony and intemperance, while involving pleasure (a sensitive appetite issue), ultimately abuse the nutritive function and harm the body-soul union. Thomistic asceticism thus recognizes that, although spiritual life is primary, it “does not require that the body be despised, but that it be ruled and well-ordered” (an idea implicit in Aquinas’s view of original justice, where the body perfectly obeyed the soul).

In summary, the vegetative level is about the maintenance of life. It provides the living platform on which all higher operations play out. A healthy ascetical regimen will respect this level by avoiding extremes that damage the body (Aquinas even lists “sleep and baths” as legitimate remedies for spiritual melancholy), while also curbing any disordered preoccupation with bodily indulgence through the virtue of temperance. The motto here is “Grace builds on nature”: we first allow the vegetative nature to function properly, then build our moral and spiritual striving upon it.

2. Sensitive Powers – External and Internal Senses

Above the vegetative, we come to the sensitive powers, which are characteristic of animal life. Sensation endows a living being with awareness of the environment and of self, enabling it to pursue what is beneficial and avoid what is harmful beyond the automatic responses of plants. Aquinas, following Aristotle, divides the sensitive powers into external senses and internal senses.

• The external senses are the familiar five: sight, hearing, smell, taste, and touch. Each is a “proper sense” directed to a specific range of sensible qualities: e.g. sight to color and light, hearing to sound, etc. Through these, the soul receives forms or likenesses of external things – for example, the colors of an apple or the sound of a bell – by means of bodily organs (eyes, ears, etc.). Aquinas notes each sense has a proper object (like color for sight, sound for hearing) and cannot perceive the object of another sense. In Thomistic understanding, the senses are passive in that they are activated by stimuli (light waves, air vibrations) impacting the organ, causing a change that the soul registers as a perception. Our external senses give us the raw data about the world – the “facts” of color, shape, temperature, flavor, and so on.
• The internal senses are more nuanced. They are the soul’s powers to process and integrate the data from the external senses and to go beyond immediate sensation. Aquinas (drawing from Greek and Islamic philosophers) commonly lists four internal senses: (a) the common sense, (b) the imagination (also called phantasy), (c) the estimative (in animals) or cogitative power (in humans), and (d) memory.
  • The common sense (sensus communis) is not “common sense” in the modern meaning of sound practical judgment, but a perceptual power that combines and coordinates the input of the five external senses. It allows an animal to perceive a unified object (e.g. that “this thing” is simultaneously red, fragrant, and sweet – rather than just disjointed patches of color and odor). It also enables awareness of sensing itself (you not only see, but know that you are seeing). Aquinas places the common sense as the ground for higher-level perceptual judgments, like distinguishing one sense’s objects from another’s and integrating them.
  • The imagination is the power to form and retain images (phantasms) of things perceived. When an object is no longer present, you can still “see” it in your mind’s eye – that is imagination at work. Aquinas describes imagination as a “storehouse of forms received through the senses”. It’s critical for all thinking, since our intellect works on the basis of these phantasms (we cannot think about a tree without some mental image or concept, which originates from imagination). For animals, imagination enables them to continue responding to things absent (a wolf can remember the appearance of prey even when none is in sight). For humans, imagination is even more powerful: we can recombine images creatively, envisage never-seen scenarios, and so forth. In spiritual practice, controlling the imagination (e.g. guarding against persistent fantasies or images that incite temptation) becomes important. The imagination can either support reason (as in envisioning holy scenes during prayer) or distract and distort it (as in daydreams or lustful fantasies), so self-discipline often involves training one’s imagination to be a help not a hindrance.
  • The estimative power in animals (or cogitative power in humans) is the ability to apprehend the meaning or value of sensed objects beyond their mere appearance. For example, a sheep instinctively recognizes a wolf as dangerous and “naturally” fears it, or a bird knows that bits of straw are useful for nest-building. These are not judgments based on the wolf’s color or the straw’s smell (the external senses provide those), but on non-sensory intentions like harmfulness or usefulness. Aquinas says animals have a natural instinct (instinctus naturalis) to perceive these practical signification of things – this is the estimative power. In humans, we also need to evaluate things under aspects not directly given by senses (e.g. this mushroom is poisonous, that person is trustworthy), but instead of sheer instinct, we rely on a rational process of comparison and reasoning. Thus, the human equivalent of the estimative is called the cogitative power or “particular reason”. It works in conjunction with our intellect, allowing us to size up particular situations in light of past experience and innate tendencies. Medical theory in Aquinas’s time even assigned this cogitative faculty to a specific brain region (the “middle cell” of the brain). When you intuitively feel that a certain face is friendly or that a certain decision is dangerous based on experience, your cogitative power is at play linking sense images with value-laden intentions. This internal assessment is crucial for moral decision-making: it feeds the rational will with context (for instance, “this looks good, but I sense it’s deceitful”). Training one’s particular reason often means learning from experience – for example, correcting naive judgments (“not all that glitters is gold”) so that our immediate appraisals of situations become more reality-based and virtue-based.
  • Memory is the power to store not just images (that’s imagination) but also the intentions or meanings associated with those images. It allows an animal or person to recall what was previously experienced as good or bad. A dog, for instance, remembers that a certain tone of voice signaled punishment, or a child remembers that the stove’s red glow meant “hot!” Aquinas notes that memory in animals is tied to particular intentions like these, often marked by some emotional resonance (something was fearful, pleasurable, etc.). In humans, memory is enriched by our intellectual capacity to reflect on the past. We not only retain experiences but can deliberately recollect them and recognize them as past (Aquinas says memory in humans observes the formal aspect of past-ness, which is a kind of intention). Strong memories often shape our current passions – e.g. a remembered injury can provoke fresh anger or sadness long after the event. Thus, part of ascetical self-knowledge is examining how our memories (and the subconscious associations we’ve built) might be inclining us toward certain emotional reactions or habits. Healing of memories and re-interpreting past events in the light of reason and faith can be a profound part of spiritual growth.

In Thomistic psychology, these internal senses explain a lot of our “inner world.” They account for how we can still fear or desire things not immediately present, how we can dream or imagine freely, and how animals achieve goal-directed behavior without reasoning. For self-reflection, it’s useful to identify these faculties at work: Are my fears coming from a rational assessment, or from an imagination run wild? Am I judging this person by instinctual bias (cogitative) or truly by intellect and charity? Am I clinging to an old image in memory that triggers disordered passion? Bringing the data from these senses into the light of reason is a key ascetical task. Aquinas emphasizes that while these powers are non-rational, in humans they are meant to be subordinate to reason’s governance. We will discuss that ordering shortly, but first, we must introduce the appetitive powers – the seat of our passions and desires – which intimately cooperate with the senses.

3. The Appetitive Powers – Passions and Desires

Once something is perceived by the senses (external or internal), the next natural step is an affective response: the soul is drawn toward what appears good or repelled from what appears harmful or bad. This responsive faculty is called the appetite (from Latin appetitus, “seeking”). In Thomistic philosophy, every cognition is followed by some appetite – even the lowest forms of life have a kind of “appetite” in that they tend toward what suits their nature. In humans and animals, the appetite at the sensory level is experienced as the passions or emotions.

Sensitive Appetite: Aquinas divides the sensitive appetite into two distinct powers, because we respond to good vs. evil in two different ways. These two modes are the concupiscible and the irascible appetite. The concupiscible (from concupiscere, “to desire”) is the seat of the simpler emotions of love and aversion, desire and avoidance, pleasure and pain. It regards good or evil simply, as pleasing or displeasing to the senses. The irascible (from irasci, “to grow angry” or by extension “spiritedness”) is the seat of the arduous emotions – those that kick in when there is some obstacle or difficulty related to attaining a good or avoiding an evil. It gives us the capacity for aggression, courage, hope, anger and the like, which rise up when mere simple desire is insufficient (for example, when the good we seek is hard to get or the evil we fear is formidable). Aquinas uses a vivid analogy: the concupiscible puts us in motion toward a basic attractive good (like food or comfort) or away from basic pain; the irascible is like a defender or fighter that “rises up” to remove obstacles or threats to those basic inclinations. They are distinct powers because sometimes they conflict – for instance, your concupiscible appetite might want to flee danger to avoid pain, while your irascible appetite (courage) pushes you to face the danger to attain a higher good. Or vice versa: the sight of a delicious cake (concupiscible attraction) might be countered by the irascible power’s emotion of shame or anger at oneself for breaking a diet, giving strength to resist. Aquinas notes “the passions of the irascible appetite counteract those of the concupiscible” in many cases. A well-formed character will have these two sub-appetites balanced and working together under reason: e.g. concupiscible love (for something truly good) will enlist irascible courage to overcome difficulties in attaining it, and irascible anger at genuine injustice will still be tempered by concupiscible gentleness or mercy so it doesn’t become cruel.

The Eleven Passions: How exactly do these emotions array themselves? Aquinas, systematizing Aristotle and the Stoics, identifies 11 basic passions (species of passion) – six in the concupiscible and five in the irascible appetite. They come in logical pairs of opposites (except one). In the concupiscible we have:

• Love (amor) and Hatred (odium) – the fundamental inclination toward a sensed good or aversion from a sensed evil. Love is the response to something as pleasing or suitable, hatred to something as unpleasant or harmful. (In animals this is rudimentary, in humans it can include affection or disgust emotionally.)
• Desire (desiderium) and Aversion (aversio) – if the beloved good is not yet present, we desire or long for it; if a hated evil is not yet present, we feel aversion or a “shrinking away” from it. This assumes the object is attainable/avoidable. If the object is present, these give way to the next pair.
• Joy or Pleasure (laetitia / delectatio) and Sorrow or Pain (tristitia / dolor) – when the desired good is attained, the soul rests in it with delight or joy; when the feared evil is present or the good lost, the soul experiences sorrow or distress. (Aquinas often uses “pleasure” for bodily delight and “joy” for a more spiritual or emotive delight, but in passions they overlap.) Sorrow is the emotional experience of present evil (ranging from minor sadness to acute pain).

In the irascible appetite, the passions presuppose that the concupiscible has presented something as desirable or hateful, but with difficulty attached. They are:

• Hope (spes) and Despair (desperatio) – regarding an absent good that is difficult but possible (hope) or judged impossible (despair) to attain. If a good we desire seems achievable despite obstacles, we feel hope (an uplifting, urging passion toward it); if it seems unattainable, we feel despair or dejection and cease pursuing it.
• Fear (timor) and Daring (audacia) – regarding an impending evil or danger. Fear is the passion when a looming evil seems unavoidable or overwhelming; it makes us want to flee or shrink. Daring (or courage as a passion) is the opposite: an aggressive forward movement of the soul when a threatening evil is faced as conquerable. For instance, seeing a predator might instill fear (if we doubt our ability to overcome) or daring (if we are roused to fight).
• Anger (ira) – a unique passion with no direct opposite in Aquinas’s schema. Anger arises when a present evil (particularly an injury or injustice) has been inflicted and there is a desire for revenge or retribution. It combines aspects of concupiscible sorrow (a hurtful evil is present) with irascible boldness (one seeks to aggressively right the wrong). Aquinas notes anger “has no contrary passion” because it is triggered by a complex situation (present evil coupled with a future good of vengeance).

Under these eleven basic types, Aquinas contends all our emotional stirrings can be categorized. This taxonomy is useful for self-examination: it helps to put a name to what one is feeling and to understand why that passion arises (e.g. “I am feeling despair – which means my concupiscible appetite still wants a good, but my irascible appetite judges it unattainable”). Each passion also has a rational aspect in humans: what do I consider “good” or “bad” here? Often we find our passions are responding to an apparent good or evil that our mind has presented to us. If the mind’s judgment is flawed (valuing a trivial pleasure as a great good, or seeing a small inconvenience as a great evil), the passions will be disproportionately strong or misdirected. Thus, mapping passions leads directly to the need for reason’s rule. Aquinas emphasizes that in man, unlike brute animals, the sensitive appetite’s movements ought to be governed by reason and will. The passions are not blind, amoral forces; they “partake of reason in some sort” when we deliberately shape or endorse them. They can and should be educated.

The Passions and Moral Good: A crucial Thomistic insight is that passions are not inherently sinful or virtuous in themselves, but derive their moral quality from how they relate to reason. Aquinas states three key points: (1) Considered just as natural, physiological responses (“motions of the sensitive appetite”), passions are morally neutral – we share them with animals, and by themselves they do not merit praise or blame. (2) However, in a human being, passions are seldom “just themselves”; since we have reason, our passions can be “commanded by and referable to reason”. When we indulge a passion against our better judgment, or arouse a passion to help accomplish a good act, the passion becomes voluntary and enters the sphere of morality. We are responsible for those passions we consent to or deliberately foster (or those we fail to check with will). Hence Aquinas can say the passions, insofar as they are voluntary (either by direct will or by “not being checked” by will), can indeed be morally good or evil. (3) Far from teaching a Stoic suppression of emotion, Aquinas holds that well-ordered passions are not only not obstacles to virtue, but positively augment virtue. “Passions under the command of reason…are an indispensable component in the doing of morally good acts,” as one scholar summarizes Aquinas. When we love the right things, desire what we ought, and feel joy in doing good, our sensitive appetite contributes energy and “warmth” to virtue. Aquinas even says that a human act is not perfectly virtuous unless appropriate passion is involved: “since pleasure perfects operation as its end, an operation cannot be perfectly good unless there be also pleasure in good”. The truly temperate person, for example, takes measured pleasure in healthy things and enjoys being moderate; a just person rejoices in giving others their due; if one felt zero inclination or satisfaction in doing good, it would indicate a lack of full integration (perhaps a will doing duty with a cold heart). In short, reason is meant to rule the passions, not to eradicate them.

Aquinas often contrasts his view with the Stoics: the Stoics treated all passions as if they were “diseases of the soul” that inherently disturb virtue. Thomas agrees that disordered (inordinate) passions are like diseases, weakening the soul. But he argues that passions within the order of reason actually strengthen good action: “Passion that follows the judgment of reason, instead of preceding it, _perfects the goodness of an act”. For example, antecedent passions (those that flare up before or against reason’s judgment) can cloud the mind and diminish voluntariness – such a passion “pulls reason away” from considering what is truly good, making even a good act less praiseworthy or a bad act less culpable due to impaired judgment. By contrast, consequent passions (those deliberately stirred or permitted by reason) add to the act’s merit – they reveal a holistic commitment of the person to the good and often make execution more effective. “The virtuous man is at peace with his own passions… his sensitive power is subject to reason to such an extent that it obeys reason’s prompting, or at least does not resist…he always acts according to reason and does not readily have regrets”, one commentator writes, distilling Aquinas. In such a person, what the mind recognizes as good, the heart also feels as good – and this harmony produces _spiritual joy and integrity.

From this, we see that handling the passions is not about extinguishing them, but about educating and moderating them. Each passion has a rightful place: fear guards us from real danger, anger can motivate justice, love draws us to what is truly good, etc. But each needs the light of reason to guide it toward the correct object and measure. Ascetic practice, then, involves neither indulging passions unchecked nor suppressing them entirely, but training them like a team of horses under a charioteer. Reason (the charioteer) must lead, but the horses’ strength (passional energy) propels the chariot faster than reason alone could move.

4. The Locomotive Power – Turning Desire into Action

Between the realm of inner passions and the execution by the body lies the locomotive power – the ability to actualize motion from place to place. This faculty, though not discussed at as great length as others, is important: it’s what allows an animal or person to carry out the behest of appetite. After all, what good would it be for a deer to feel fear of a predator if it could not run away? Or for a human to desire knowledge if he could not move to seek a book or a teacher? Locomotion is the bridge from internal appetite to external action. Aquinas lists it as one of the five general powers of the soul (plants lack it, most animals have it, humans have it).

In humans, the locomotive power is thoroughly permeated by voluntariness. We do not wander aimlessly by pure instinct; ideally, our movements are directed by our will and practical reason. Aquinas observes that in brute animals, a passion in the sensitive appetite (like fear or lust) immediately triggers bodily movement: a sheep sees a wolf (estimates danger) and automatically flees. But humans have a superior appetite (will) that can intervene. Even if fear stirs in us, we are capable of standing our ground by will’s command. “Man is not moved at once, according to the irascible and concupiscible appetites, but awaits the command of the will, which is the higher appetite”, Aquinas explains. In technical terms, the will (a rational appetite) is like a first mover in the order of action, and the muscles obey the will’s command even if the passions are urging something else. This is a powerful aspect of human dignity: we can choose to act contrary to our spontaneous feelings – e.g. force our feet to walk into a dentist’s office despite fear, or refrain from striking someone despite anger. The sensitive appetite “is not sufficient to cause movement, unless the higher appetite consents”.

In practice, the locomotive power is perfected by the virtue of prudence and the habit of decisive will. Some people struggle with what we might call acedia (spiritual sluggishness) or simple laziness – knowing the good but failing to get up and do it. Training the will to promptly translate good intentions into movement is a key ascetic challenge. It might be as simple as obeying the morning alarm clock (overcoming the body’s inertia out of reason’s decision to start the day in prayer), or as complex as building consistent habits of attending duties without procrastination. While Aquinas doesn’t classify “locomotion” under moral virtues directly, it is implied that a rightly ordered soul integrates the body’s motions under the governance of reason. Even posture and gestures can reflect interior order or disorder! A composed, temperate person will habitually carry themselves and move in a way that reflects inner calm and purpose, whereas an impulsive or intemperate person’s movements may be hasty, erratic, or sloppy. Thus, attention to how we physically enact our choices (our external conduct) is not trivial: it solidifies virtue or vice. Ascetically, this might mean disciplining oneself to bodily acts that reinforce interior decisions – for example, kneeling to pray even if one doesn’t “feel like it” (here, the will moves the body and even can stir piety by posture), or conversely, deliberately relaxing bodily tension when angry as a way to temper the passion. The partnership of body and soul is such that motion can either obey reason or exacerbate passion. In sum, locomotion is the final common pathway of the soul’s command over the body: in a well-ordered soul, the body is a faithful servant, executing what the higher faculties have judged and desired, *“as at the soul’s command both hand and foot…are moved at once”. Achieving that level of prompt obedience of the body is a fruit of much practice and virtue.

5. Rational Powers – Intellect and Will

At the pinnacle of the soul’s hierarchy stand the rational powers, which are unique to spiritual beings (humans and angels). These are the faculties of intellect (reason) and will, through which we engage with truth and goodness as such. Aquinas calls the human being’s rational soul the “intellectual soul” to highlight that our defining feature is the ability to know universal truth and to freely direct ourselves to ends under the guidance of reason.

Intellect (Reason): The intellect is the power by which the soul understands and knows. Unlike the senses which deal with concrete, particular data, the intellect can grasp universals – the natures of things, abstract concepts (like justice, humanity, triangle), and even immaterial truths (like mathematical objects or philosophical insights). Aquinas carefully argues that the intellect is a distinct power of the soul, not the essence of the soul itself. If our soul were its intellect, we would be pure intellects (like angels) and have no other operations. But clearly the human soul has vegetative and sensitive operations too; thus intellect is one faculty of the composite human soul. The intellect has two primary modes: speculative (contemplating truth for its own sake, asking “What is so?”) and practical (deliberating truth for action, asking “How to attain a good end?”). Aquinas also distinguishes the agent intellect (which abstracts universal ideas from the phantasms provided by imagination) and the possible intellect (which receives and holds these ideas). In everyday terms, our intellect first grasps basic principles (e.g. metaphysical truths, logical axioms, or moral first principles like “do good, avoid evil”), and then discursively reasons to conclusions or makes judgments. It can reflect on itself (you can have thoughts about your thoughts). It also includes specialized habits/faculties like synderesis (the habitual knowledge of fundamental moral truths – a kind of innate conscience) and conscience (the act of applying moral principles to particular cases).

For Aquinas, the intellect is oriented toward truth – it is fulfilled by knowing reality as it is. Its highest act is contemplation of the highest truths (ultimately the vision of God, who is Truth itself). But even on the natural level, the intellect’s excellence lies in aligning our understanding with reality (as God created it). Thus, ignorance and error are deficiencies in this power. Due to the wound of original sin called ignorance, our intellect has difficulty knowing truth readily. We overcome this by study, learning, and divine illumination through faith.

Will: The will is the rational appetite – the power by which the soul chooses and loves. As the intellect aims at truth, the will aims at goodness. More precisely, the will is that faculty by which whatever the intellect presents as a possible good, the soul can freely desire, intend, and seek it. It is often called our capacity for free will. Aquinas teaches that the will is “a power of the soul” distinct from the lower appetites. Unlike the concupiscible/irascible appetite which are tied to particular sensory goods (food, comfort, safety, etc.), the will reaches the universal good as apprehended by reason. This means the will can desire not just the apple, but health, virtue, knowledge, God – things which the senses cannot fully grasp but reason can present as worthwhile. The will is in a sense boundless in its scope: ultimately, it seeks happiness or beatitude in the fullest sense, which in Aquinas’s theology can only be satisfied by the infinite Good (God). All particular choices of the will are oriented toward some perceived good, but not every perceived good is truly good. The will’s freedom lies in its ability to choose among various apparent goods, or to defer choice, etc., under guidance of reason.

A key Thomistic principle is that intellect and will work together. The intellect presents (to the will) an object as good or desirable under some description, and the will, moved by this good, chooses and moves the person to act. Then through action or imagination the intellect might get new information, present new considerations, and the will may choose again, and so on – a dynamic interplay. In a perfect scenario, the intellect correctly recognizes the true good in a situation, and the will promptly chooses it; the passions then align to provide emotional drive, and the body executes the choice. That is an image of order. However, due to the wounds of sin, the will suffers from malice, a tendency to turn away from the proper good (God and righteousness) toward lesser, selfish ends. This wound of malice means our will can be perversely attracted to evil (under some mistaken notion of it being good for us). Overcoming malice requires healing by virtues – especially charity (directing the will to love God above all) and justice (inclining the will to give each his due and seek righteousness). We’ll elaborate on virtues in the next section.

It’s important to note Aquinas’s teaching that reason and will have a natural primacy over the lower powers. In the original state of humanity (prior to sin), “the reason had perfect control over the lower parts of the soul, and reason itself was subject to God”. This original justice meant the will obedient to God, and the passions obedient to the will/reason. After the Fall, this harmony was lost: “all the powers of the soul are left destitute of their proper order”. The result is internal conflict – “the flesh lusts against the spirit”, as St. Paul says. Yet even in fallen man, some vestige of hierarchy remains: the intellect can still instruct the passions and the will can command the body, albeit imperfectly. Aquinas uses a political analogy: in a human person, the soul rules the body despotically (the body’s members have no independent will against the soul’s command), but the intellect rules the passions “politically or royally”, as a king over free but subordinate citizens. The lower appetite can resist reason’s command to an extent (just as citizens can disobey a king), yet it is naturally made to be guided by reason. We “feel” this daily: we argue with ourselves, “I shouldn’t eat that cake” (reason) while desire insists “but I want it” (passion); or fear says “run” while will says “stay”. This conflict is not absolute or permanent – with training, the passions learn to obey more readily. The ideal is captured in Aquinas’s phrase: “the irascible and concupiscible powers obey reason”. We know this obedience is possible because we can actually moderate passions by thought: “by applying certain universal considerations, anger or fear or the like may be modified or excited” in us. For example, when angry you might calm yourself by recalling “anger yields nothing but folly”, or when afraid you might bolster courage by thinking “this duty matters more than my comfort”. These are the intellect presenting judgements that literally change how one feels. Thus, reason can govern, if we assert its voice. The will, too, has a role: we can choose to act contrary to our passionate impulse (e.g. despite anger, speak gently), effectively telling the passions “you are not in charge.” Over time, well-governed passions become more habituated to follow reason’s lead (this is the development of virtue).

To sum up the rational powers: Intellect is our guiding light, discerning truth and defining what is truly good; Will is our executive power, choosing and loving in accordance with that perceived good. Together they constitute the spiritual core of the person (sometimes referred to collectively as the “mind” or the “rational soul” in Aquinas). They are the faculties by which we are most in the image of God (who is infinite Intellect and Will, i.e. Logos and Love). All lower powers are meant to serve these higher ones. The more our bodily and emotional life is harmonized with reason and will, the more fully human (and happy) we are. But if the rational faculties are neglected or if the will chooses against reason (sin), the soul falls into inner disharmony and moral failure. In the next section, we will explore how the overall order or disorder among these powers impacts our moral and spiritual life, and what the Thomistic tradition prescribes for restoring order.

III. Order and Disorder in the Soul: The Thomistic Framework

Having mapped the soul’s powers, we now consider the order among them. Thomistic anthropology is profoundly hierarchical: the powers are arranged from lowest to highest, with each higher power meant to direct the lower towards the fulfillment of the whole person. In the human soul, reason is meant to reign over the passions and bodily impulses, and the will (guided by reason) is meant to command our actions. When each power functions in proper relation – vegetative serving the needs of the body, senses accurately informing the intellect, passions obeying reason’s guidance, will choosing the true good presented by intellect – then the person lives in a state of inner harmony. Aquinas calls this original state original justice, and describes it succinctly: “As a result of original justice, the reason had perfect hold over the lower parts of the soul, and reason itself was subject to God”. In other words, the human being was created with a fourfold harmony: reason obedient under God’s wisdom, the will obedient to reason/God (loving what should be loved), the passions obedient to the will and reason, and the body obedient to the soul.

The Disruption of Original Order: With original sin, this harmony was shattered. Aquinas teaches that when our first parents turned their will against God (the higher rejecting the Highest Good), the consequence was loss of original justice, leaving the lower powers in rebellion against the higher. He speaks of four wounds inflicted on human nature corresponding to the four cardinal faculties that had been harmonized:

• Ignorance in the intellect (a wound to the faculty of prudence/truth) – our reason became dimmed especially in practical and spiritual matters. Now we have difficulty knowing important truths, we fall into error or confusion, and reasoning requires labor. This counters the ease of knowing the true good.
• Malice in the will (a wound to justice/charity) – an inclination of the will to selfish or perverse ends, deviating from the good it ought to seek. We experience this as hardness of heart or disordered self-love that biases our choices.
• Weakness or frailty in the irascible appetite (a wound to fortitude) – the courage and endurance of the soul is weakened. We find it hard to persevere in arduous good; we easily succumb to difficulties or fears. The spirited drive doesn’t follow through as it should, making us spiritually limp.
• Concupiscence (in a specific sense) in the concupiscible appetite (a wound to temperance) – an unruly desire for sensible pleasures beyond reason’s order. The lower desires (for food, sex, comfort, etc.) pull insistently, not readily submitting to rational moderation. This is often what people mean by “concupiscence”: a general inclination to sensual and self-indulgent pleasures that resists discipline.

These four wounds – ignorance, malice, frailty, concupiscence – concisely describe the disorder we all experience internally. St. Paul’s lament “I do not do the good I want, but the evil I do not want is what I do” (cf. Rom 7:19 ) captures the dynamic: “I see another law in my members fighting against the law of my mind”. Aquinas indeed quotes that verse to acknowledge that the sensitive appetite can “resist reason” at times. Importantly, he clarifies: just because the passions sometimes rebel, “we must not conclude that they do not obey [reason]” at all. In fact, the moral life is largely about re-establishing order: we strive to have our “lower appetites partake of reason” (Aristotle’s phrase) so that gradually, the passions in general align with what the mind knows is right, even if perfect alignment isn’t attained in this life.

Moral Order: Aquinas states that “all the passions of the soul should be regulated according to the rule of reason, which is the root of the virtuous good.”. This regulation by reason is what the moral virtues accomplish, as we will see in the next section. When reason’s rule is reasserted, the person grows in integrity – literally an inner wholeness or consistency. Aquinas describes the virtuous man as one whose whole being is oriented to the same ends: “he keenly feels his own sorrows and joys since the same thing is painful or pleasant to his whole being (both the sensitive and intellectual part) and not one thing to one part and another to another”. This unity of feeling and reason is a sign of healing: for example, a temperate person finds moderate eating genuinely pleasurable and gluttony repulsive, whereas an intemperate person’s concupiscible appetite (love of excessive food) might clash with intellect (which says “this is unhealthy”) causing inner tension or later regret. The goal is that what reason approves, emotion embraces, and what reason condemns, emotion likewise rejects. Aquinas goes so far as to say if someone felt absolutely no emotional aversion to evil or attraction to good, that would indicate a flaw: “those who are without righteous sorrow or rightful joy in response to evil or good are lacking in virtue”. Thus, in reordering, we don’t kill emotions – we convert them.

Signs of Disorder vs. Order: For practical self-examination, we can outline some hallmarks of disintegration versus integration:

• When the soul is disordered, lower impulses routinely “negotiate” with or override higher commitments. For instance, one might regularly skip prayer or duty for the sake of a bodily pleasure or out of sloth – indicating that the concupiscible appetite is effectively ruling the will, instead of vice versa. Aquinas would see this as the inversion of the proper hierarchy (a form of intemperance or acedia). If “that which is lower does not obey that which is higher,” the result is sin and unrest. The person experiences inner contradiction: guilt (because reason still recognizes the betrayal of the true good), loss of self-respect, and often a greater difficulty doing good next time (since vice weakens the inclination to virtue).
• In an ordered soul, the higher leads the lower with relative ease. One notable measure is consistency in acting according to one’s deliberate resolutions without feeling constantly “pulled aside” by contrary emotions or urges. For example, the ordered person can carry out their plan of rising early to pray with minimal internal fuss – the body and concupiscible appetite have been habituated to accept reason’s direction that prayer is a higher good than extra snoozing. Aquinas describes this ideal using Aristotle’s notion of politic rule: the passions freely obey like good citizens, occasionally offering their own suggestions (feelings) but fundamentally respecting reason’s leadership. There is a peace that results: “the virtuous man is not led by the passions…thus he is at peace with himself”. He does not experience the same acute inner war between “law of mind” and “law in the members,” or if a conflict sparks, it is quickly settled by a firm will.

It must be stressed that complete restoration of original order is not possible by human effort alone. The theological doctrine is that only by supernatural grace (especially in the glory of heaven) will our powers be perfectly healed (even the saints on earth felt some rebellion of the flesh). But substantial progress is both possible and expected through virtue, prayer, and ascetical practice. The sensitive appetite can be trained to “listen” to the intellect as a horse to a rider. Aquinas acknowledges that the sensitive appetite “has something of its own” by which it can resist (since it also is stimulated by imagination and bodily changes). This means we should not be surprised by residual resistance – e.g. a lustful thought or sudden fear arising unbidden. Such first movements of passion occur “pre-reflectively,” and Aquinas does not count them as sin if not consented to. They are symptoms of the wounded nature. The task is to prevent these first movements from becoming consent to disorder. If reason catches the rising passion and either moderates it or redirects it appropriately, then order is maintained or swiftly reestablished. In practical terms: feeling a flash of anger is not a sin, but deciding to wallow in it or act on it unreasonably is. Similarly, experiencing sexual attraction is not immoral, but consenting to entertain lustful fantasies would be disorder.

Aquinas also notes a fascinating point: sometimes even a well-ordered passion can temporarily impede reason’s operation, yet without being immoral. For example, “in conjugal intercourse, though the pleasure be in accord with reason, yet it hinders the use of reason on account of the accompanying bodily change”. He compares it to sleep: when you sleep (which is natural and often reasonable to do), your higher reasoning powers suspend, but that’s not sinful – reason itself judges that at times it’s proper to rest or to engage fully in a bodily act. So the Thomist perspective isn’t that we must be coldly rational at every second; rather, reason should dictate the appropriate times and limits for descending into purely sensual pleasure or emotion. “There is a time to weep, and a time to laugh” – during the laughter or weeping, the emotional movement might flood awareness, but overall it remains within reason’s ordinance. In contrast, disorder would be e.g. indulging a pleasure when reason says it’s the wrong time or measure (like laughing loud in a solemn ceremony, or sleeping when one should be working). Thus, the measure of order is fidelity to reason’s proper order in the big picture.

Concupiscence and Spiritual Combat: A major focus of asceticism is dealing with the concupiscence that remains even after baptism (which forgives sin but leaves the inclination to sin). As Aquinas puts it, concupiscence is natural to man insofar as it obeys reason, but insofar as it goes beyond reason’s bounds, it is “unnatural” (a privation of original nature). We experience concupiscence as an ongoing vulnerability – a tinder for temptation (“fomes peccati”). Recognizing this humbly is crucial; it means we must be vigilant and not trust our lower desires to lead the way. Reason enlightened by faith must be the compass. One practical upshot: because the lower appetite can be stirred even when reason doesn’t want it (e.g. sexual desire from a sudden image, or panic from an unexpected noise), we often need to prudentially avoid occasions that overstimulate the passions beyond what we can readily manage. This is not cowardice but wisdom: since “the sensitive appetite depends on organic conditions not fully under reason”, we steer our environment (as far as duty allows) to support virtue – for example, avoiding media that provoke lustful reactions or keeping away from persons who incite our anger or envy too strongly, at least until we’re stronger. Such strategies belong to traditional ascetic prudence: remove the fuel if you don’t want a fire. Over time, as virtue grows, what once was dangerous may become less so (e.g. a recovering alcoholic gradually finds that the passion for drink no longer flares at the sight of wine), but humility remains – we never assume invulnerability, but continuously rely on reason and grace.

In summary, Thomistic thought presents a clear teleology of the soul’s powers: the lower exist for the higher, and the higher for the highest (which is God). Disorder is when this direction is inverted (when, for instance, we live as though bodily pleasure were the highest end, subordinating intellect and violating God’s law for its sake). Order is beautifully expressed by Aquinas: “All the passions of the soul [must] be regulated by reason…and directed to the good of the human person”. The human person’s total good includes bodily and emotional well-being, but always integrated under spiritual and moral truth. Morality consists not in suppressing natural urges but in training and using them for the total good, as one interpreter of Aquinas succinctly says. The final end of man is not the extinction of his passionate nature, but its perfect subordination to and harmony with rational love of God, the supreme Good. “The virtuous man is at peace with himself” precisely because each part of his soul is doing its God-given role, neither idle nor mutinous.

Having considered the natural powers and their disorder, we now turn to how we remedy that disorder: namely, through the cultivation of virtues with the help of grace. Virtue is the Thomistic answer to the question, “How do I get my soul’s parts to cooperate under reason?”

IV. Virtues: The Training of the Soul’s Powers

Virtue in Thomistic philosophy is a habitual disposition that perfects a power of the soul, enabling it to act easily and well. Since each faculty (intellect, will, irascible appetite, concupiscible appetite, etc.) has its own kind of operation, each requires a virtue (or set of virtues) to reach its optimal function. Aquinas, following Aristotle and Scripture, outlines the four cardinal virtues – Prudence, Justice, Fortitude, Temperance – precisely as perfections of the four main human faculties. He ties them to the “four wounds” as healing medicines. Let us examine these in turn:

• Prudence perfects the intellect (practical reason). It is the habit of right reasoning about things to be done – seeing rightly what truly benefits our life as a whole and the proper means to achieve it. Prudence heals the wound of ignorance by giving insight and good deliberation, so we are less likely to mistake evil for good or choose rashly. A prudent person accurately reads reality (both moral principles and concrete circumstances) and makes sound judgments, effectively “re-tooling” the intellect to its pre-fall strength in guiding life. Prudence in action looks like clear-sighted decision-making: neither naively idealistic nor cunningly selfish, but objectively wise. It governs the application of all other virtues by directing them to the good. Cultivating prudence involves learning (studying moral and practical wisdom, getting counsel), remembering past lessons, and attentiveness to reality (not being swept by passion or ideology). In self-reflection, prudence asks, “What is my ultimate goal, and does this particular choice lead me toward it or away from it?” In ascetic struggles, prudence might suggest gradual tactics (like weaning off a vice with interim steps) or bold ones (like cutting off an occasion of sin immediately), depending on what reason judges will lead to lasting virtue. We saw an example of such discernment in the imaginary dialogue from the user: distinguishing a “controlled descent” in habits from a self-deceptive indulgence hinged on prudently judging the direction of the will (using criteria like “Am I doing this lesser thing as a medicine to reach a good, or just as an excuse to keep a pleasure?”). That kind of fine judgment is precisely prudence at work.
• Justice perfects the will. It is the habit of consistently willing what is right, giving each their due – to God, to neighbor, and to oneself in the proper sense. It heals the wound of malice (the will’s tendency to evil) by inclining the will to the truly good and to fairness. A just person loves what is right and is resolved to act accordingly (e.g. to fulfill promises, respect others’ rights, obey God’s law). In terms of self-governance, an aspect of justice is obedience to God and proper self-love (willing the authentic good for oneself, which is ultimately virtue and beatitude) – this rectitude of will counters the malice that prefers lesser goods or selfish satisfaction over God’s will. Cultivating justice means practicing honesty, responsibility, gratitude, religion, obedience to legitimate authority, etc., until doing the right thing becomes “second nature.” When it comes to internal struggles, justice in the will is what must rally to say “No, this is _wrong, I shall not consent”_ even if passions clamor. It’s that firmness to adhere to the moral law and charity. In ascetic terms, one might speak of “justice toward God” as _religion_ (devotion, putting God first) and “justice toward self” as rightly ordering self’s parts (since as rational creature you owe it to your nature to keep it ordered). Aquinas would say the notion of “owing oneself a well-ordered life” is metaphorical, but it captures the idea that we are not treating ourselves justly when we allow lower cravings to ruin our true good. So justice, broadly, helps motivate the will to impose moral order: “This disordered desire is cheating my soul of its due excellence; I _owe it to my calling and to God to resist.”_ Such an internalized sense of duty and right is the mark of a will healed by justice.
• Fortitude (courage) perfects the irascible appetite. It enables steadfastness in the pursuit of arduous goods, taming the passion of fear and moderating the passion of daring or anger so that we neither flee what reason says must be faced nor recklessly risk what reason says should be avoided. Fortitude heals the wound of weakness by strengthening our resolve in the face of difficulties. A person with fortitude can persevere through trials, resist undue fears, and endure suffering for the sake of the good. This is vital in spiritual combat: many vices (from sloth to indecision) come from lack of fortitude – we give up because virtue is hard, or we compromise because we fear discomfort or human opinion. Fortitude in practice means training ourselves to tolerate hardship: small mortifications (like fasting, vigils, cold showers) historically serve to build fortitude, not as ends in themselves but as exercises – they teach the irascible part that it can push through pain and not die, it can stand firm. Also, reflecting on the rewards and meaning behind sacrifices fuels the passion of hope (the irascible’s positive motion). Aquinas ranks magnanimity (great-souled ambition for honor in virtuous things) and patience (endurance of suffering) as parts of fortitude. In daily ascetic life, fortitude is needed for consistency – e.g. continuing in prayer when it’s dry, or resisting an addiction’s pangs after the initial enthusiasm fades. It’s the virtue of the spiritual “marathon runner”. Without it, initial good impulses melt at the first sign of struggle. With it, one can echo St. Paul, “I have fought the good fight, I have finished the race”.
• Temperance perfects the concupiscible appetite. It moderates the attraction to pleasurable things of touch (primarily food, drink, and sexual pleasure) in accordance with reason. Temperance heals the wound of concupiscence (unruly desire) by restraining and rightly ordering our sensual appetites. The temperate person enjoys* pleasures in a reasonable manner, at the proper time, in the proper measure, and abstains when it’s right to abstain. Aquinas emphasizes that temperance is not a rejection of all pleasure, but a rejection of immoderate, disordered pleasures. “The temperate man does not shun all pleasures, but those that are immoderate and contrary to reason”. So a sign of temperance is the ability to take or leave bodily delights peacefully. One who is temperate with food, for instance, can enjoy a meal without overeating, but also can skip a meal or eat plain fare without distress. They have inner freedom regarding pleasure: pleasure no longer controls them either by dominating their will or by causing anxiety when absent. Achieving this often requires gradual training: fasting, refraining from indulgences, practicing modesty and chastity in conduct and thought – these are ways we wean the concupiscible appetite from childish self-indulgence. Aquinas also speaks of the “mean” of temperance: it’s not only about saying no to excess, but also about not erring by insensitivity (one should not, for example, have contempt for the goodness of food or marital intimacy in an extreme way). The truly temperate have a balanced enjoyment: they take honest pleasure in what is permitted, but are unenslaved. As Aquinas beautifully puts it, “temperance is about the desire for the greatest pleasures… It _orders these desires so that they accord with reason, and thereby helps create a beautiful soul”. In ascetic life, this virtue is often the frontline, because many beginners struggle chiefly with bodily temptations (gluttony, lust, laziness). The battle for chastity or sobriety is quintessentially a battle for temperance. By repeated acts of restraint and refocusing on higher goods, the concupiscible appetite _learns that it cannot always get its way and that life is actually better so. Over time, the intense cravings subside to a manageable level (this is the effect of virtue: what was hard becomes easier and even joyful).

In addition to these natural (or acquired) virtues, Aquinas, as a theologian, underscores the role of the theological virtues – Faith, Hope, and Charity – which God infuses and which orient intellect and will to supernatural union with Him. Faith perfects the intellect in knowing divine truth (countering ignorance in the highest matters). Hope perfects the will by fastening it on God as our eternal good (lifting the irascible appetite to endure trials for heaven’s sake, remedying weakness and despair). Charity perfects the will by conforming it to God’s love, making us friend of God and rightly ordering all other loves under the love of God (healing malice at the root, since charity is the direct opposite of the self-seeking that is the essence of sin). Charity also enkindles a rightly ordered joy in God and sorrow for offense against Him, thereby integrating passions into the spiritual life. While a full discourse on these exceeds our scope, it’s important to note: grace is indispensable in Aquinas’s view for full restoration of the soul. “Without Me you can do nothing,” said Christ – meaning, no lasting victory over our fallen self is possible without divine aid. The infused virtues elevate and strengthen the soul’s powers beyond what unaided habit can do. For example, one might by effort achieve a measure of temperance, but only with God’s grace can one attain the deep purity of heart that delights in sacrifice out of love for God (that’s temperance animated by charity). Aquinas states that original justice (the original integrity) was a gift from God, so it will take gifts from God (sanctifying grace and virtues) to fully reintegrate us.

That said, Thomistic ascetic theology does not encourage passivity. We must act and cooperate with grace. “Grace does not destroy nature but perfects it” – meaning our natural powers and efforts are the platform grace builds on. Thus, building the acquired virtues (prudence, justice, etc., by repeated practice) and simultaneously praying for and exercising the infused virtues go hand in hand. A Thomist will pray as if all depends on God, and work as if all depends on himself – knowing both are true in different senses.

Let us illustrate how virtues reorder a concrete scenario: imagine a man trying to overcome a habit of excessive internet use and impurity. Prudence first helps him recognize the real harm this habit causes (wasted time, spiritual desolation, objectification, separation from God) and to devise a plan (e.g. install filters, fill schedule with alternate activities, seek accountability). Justice moves his will to firmly commit to this plan out of duty to God and respect for self and others (no more rationalizing or half-measures – he knows he owes God better use of time and owes others pure regard). Fortitude readies him to endure the discomfort and emptiness that will come when he logs off – the restlessness, the FOMO, the cravings – and not to cave when lonely or stressed; it steels him to fight maybe many battles if he relapses, to get up again without despair. Temperance bit by bit lessens his desire for stimulation: he practices fasting from devices, redirecting urges through cold showers and exercise, training his concupiscible appetite to be content with simpler, wholesome pleasures (like real friendships, nature, prayer) instead of constant dopamine hits. Meanwhile, faith gives him the light to see this struggle in the context of salvation (it’s about his relationship with God, not just self-improvement), hope gives him trust that with God he can attain freedom and that true happiness lies ahead, and charity inflames him to persevere out of love for God (“I want a clean heart to see God” – echoing “Blessed are the pure of heart”). Over time, success signs appear: his mind becomes clearer (intellect healed), his will finds new joy in doing good and a hatred of the old sin (will aligned to true good), his lower urges quiet down to their rightful place (passions obey more readily – e.g. a tempting image he immediately dismisses without a huge internal fight), and his external life finds greater order (he uses his time well, engages in service or creativity, etc.). This is the process of virtue restoring order. It is gradual, often two steps forward one step back, but real.

The interplay of virtues also shows why a holistic approach is needed. One cannot simply will to stop a sin (justice in will) without engaging the intellect (prudence to identify triggers and solutions), and without bolstering fortitude and temperance to handle the emotional and bodily side. The Thomist view is wonderfully integrated: because we are composite beings, the remedy for sin must address every level of the soul. Hence ascetic practices: prayer (to lift intellect and will to God), meditation on truth (to enlighten intellect), examination of conscience (to sharpen prudence about oneself), fasting or bodily disciplines (to toughen fortitude and temperance), sacraments and devotions (to infuse grace and charity), acts of service (to channel passions into good action and build justice toward neighbor). Each practice targets different faculties but ultimately furthers the harmonious functioning of all.

We should mention also the concept of the Gifts of the Holy Spirit in Thomistic theology, which are like supernatural perfections of the soul’s faculties that make them docile to God’s promptings (wisdom perfects intellect/charity, understanding perfects intellect/faith, counsel perfects prudence/hope, fortitude gift elevates fortitude virtue, piety elevates justice toward God, fear of the Lord elevates temperance, etc.). These gifts help us operate under the instinct of the Holy Spirit beyond our own mode. For example, the Gift of Fortitude can carry a martyr through sufferings nature could not endure. While beyond the scope here, it’s noted to show how every faculty has both a virtue (our own good habit) and a gift (Spirit’s aid) to perfect it.

Finally, Aquinas places charity as the form of all virtues – meaning love of God should animate and direct all our virtuous efforts to the ultimate supernatural end. Ordered loves are crucial: St. Augustine said virtue is ordo amoris (the order of love). Disordering of the soul can be seen as disorder of love – loving lower things more than higher (e.g. loving pleasure more than God or neighbor). Thus, the supreme ordering principle is to “love God with all your heart, soul, mind, and strength, and your neighbor as yourself”. When charity rules, everything else gradually falls in place: we then want what God wants (healed will), see ourselves and others in God’s light (healed intellect), feel appropriately (passions aligned with what love dictates – e.g. zeal for good, holy anger at injustice, compassion for suffering, joy in righteousness), and use our bodies in service of love (not as instruments of sin). Therefore, the perfection of the Thomistic system is a holy soul, where human effort and divine grace culminate in sanctity. The saints, in Thomistic view, are the truly sane and sound humans – they have, to a heroic degree, integrated their entire soul under love and truth.

For our purposes of self-reflection and decision-making: understanding virtues gives a framework to diagnose which power of the soul needs work. If I keep knowing what is right but not doing it, perhaps fortitude or temperance is lacking (my passions overwhelm my weak resolve). If I charge passionately into actions but later realize they were foolish, I likely lacked prudence (acted without true understanding). If I habitually make time for myself but not for prayer or service, my charity and justice are wanting (my loves are disordered). So, a Thomist would advise: zero in on the virtue corresponding to your predominant struggle and develop it through concrete exercises. The result is not only stopping a particular sin but making the soul harmonious and resilient overall.

V. Practical Ascetical Discernment: Applying Thomistic Principles to Self-Governance

With the theoretical groundwork laid – the soul’s powers, the passions, the hierarchy, and the virtues – we arrive at the practical art of governing one’s soul in daily life. Thomistic asceticism is often about developing a kind of spiritual common sense or scientia regiminis (knowledge of governing) that the soul’s rational part must exercise over the self. This involves self-knowledge, self-assessment, and strategy for growth in virtue. We will outline some practical frameworks and “mental tools” drawn from Thomistic thought and the broader tradition that align with it, to help one reflect and make decisions toward ordering the soul. The aim is to inform self-reflection, analysis, and decision-making – avoiding the extremes of either semi-Pelagian self-reliance or vague quietism, and instead using one’s mind and will (illuminated by faith) to cooperate methodically with grace.

1. Examination of Conscience and Analysis of Attachments

Aquinas says “the first step in escaping an evil or attaining a good is to know it”. Regular self-examination is crucial. This isn’t navel-gazing for scruples, but a reason-guided inventory: What powers of my soul are dominating, and are they doing so rightly? A Thomistic exam might go like this:

• Assess your prayer and rational focus: Since prayer is a prime act of the rational soul (reason and will directed to God), check what interferes with it. Aquinas held that anything that consistently makes prayer repellent or hard is likely a disordered attachment. For example, if on nights when you watch certain entertainments you find you “don’t feel like praying” or you cut prayer short, that pleasure is “negotiating with God”, which is a red flag. As one might say, “that which negotiates with prayer is not neutral”. In Thomistic terms, it indicates the passion for that activity is usurping the will’s proper order (God first). So ask: Do I habitually postpone or skip spiritual duties for the sake of some pleasure or comfort? If yes, reason should mark that attachment as an enemy of order to be tackled.
• Identify predominant passions: Use Aquinas’s passion schema to name what often leads you into sin or imbalance. Is it concupiscible passions (love of food, sexual pleasure, comfort, approval) or irascible (anger, ambition, stubbornness, fearfulness)? Knowing your temperament in these terms guides you to which virtues to stress. For instance, strong anger (irascible) means focus on meekness and patience; strong sensuality (concupiscible) means focus on temperance and custody of senses.
• Rank attachments by gravity: Aquinas would prioritize by how much a thing turns you from your final end. Obviously, mortal sins (directly contrary to love of God) must go first – they are like spiritual death. But even among non-mortal things, some hinder spiritual progress more. A suggested Thomistic approach (echoing the earlier conversation example) is to evaluate each significant pleasure or pursuit in your life by five criteria (in order of importance):
  (a) Effect on your ultimate purpose (relation to God/duty): Does this thing weaken my orientation to my highest end? Concretely, “After indulging this, do I find prayer or fulfilling my primary responsibilities (state in life duties) more difficult?”. If a late-night entertainment consistently causes one to sleep through morning Mass or pray without recollection, it’s seriously disordered. If a hobby leaves one too preoccupied to attend to family or work, likewise. The highest measure is: Does it compete with my love of God and pursuit of virtue? As Aquinas said, “not all pleasures are evil, but only those which distort the order of reason” – and nothing distorts reason’s order more than stealing the time/energy owed to God or virtuous duty. So any habit that does so should be top of the reform list.
  (b) Attachment intensity: How hard would it be to give this up for a time? Aquinas remarks that the will’s clinging to a lower good can be measured by the pain at its absence. So test yourself: “Could I peacefully refrain from this for 30 days?” If the thought of abstaining causes disproportionate anxiety or a sense of great loss, your will may be inordinately attached. Our Lord’s counsel to the rich young man to give up his wealth was precisely to reveal attachment – and the man went away sad, showing he was not free. While we’re not all called to literally renounce everything, we are called to an inner freedom where we possess things without being possessed by them. So from time to time, voluntarily deny yourself even permissible delights to ensure mastery. This is the monastic practice of discipline of the appetite for lay life: skip dessert, take a day off social media, etc., and observe your soul’s reaction. If you detect rebellion or turmoil, that appetite needs further training. As a maxim: that which you cannot relinquish, owns you. A well-ordered soul can let created goods come and go without losing its equilibrium, finding its primary joy in God.
  (c) Nobility of the pleasure’s object: Is this a lower kind of good (bodily, sensory) or a higher kind (intellectual, spiritual)? Aquinas notes that bodily pleasures, especially of touch, have the greatest pull on the soul and can most enslave it if not checked. Intellectual pleasures (like reading, art, etc.) are generally less corrupting unless they involve pride or falsehood. So, as a rule, if one’s dominant attachment is to something like food, drink, sexual gratification, or material comfort, that’s a more urgent area to temper than, say, a love for chess or classical music (though anything immoderate is problematic). This is because bodily passions, when strong, tend to “drown out” reason through their intensity and physiological impact. They literally change the body (hormones, adrenaline, etc.) and thus cloud thinking. In contrast, someone attached to, say, solving puzzles might be distracted but not as senselessly carried away. So evaluate: sensual indulgences (gluttony, lust) are top priority to rein in, whereas refined pursuits should be watched for pride or time-wasting, but they rank slightly lower in raw danger to virtue. Aquinas says “flesh” in Scripture often symbolizes the sensitive appetite, and we must by the spirit subdue it. Notably, he remarks that bodily-passional pleasure tends to fetter reason more than any other experience (hence intoxication or sexual arousal can suspend reason). So keep a wary eye: if any pleasure regularly “fogs your mind” (either in the moment or by obsession outside the moment), it needs strict moderation.
  (d) Impact on virtue and growth: Does this habit strengthen or weaken my virtues? Does it make me more or less temperate, courageous, just, and prudent? For instance, engaging in a competitive video game might be neutral recreation, but if you notice it’s making you irascible or impatient (against justice/charity) or simply consuming time you should use for studious work (against prudence), it is hampering virtue. On the positive side, some pleasures or interests can be harnessed to virtue – e.g. enjoying nature can inspire gratitude to God; sports can build fortitude and camaraderie (if kept virtuous). So discern: is this activity integrated into my virtuous life, or at odds with it? Our Lord said “by their fruits you will know them.” The “fruits” of an attachment are the moral/spiritual effects it leaves. If after indulging, you’re more lethargic, irritable, less devout – that fruit is bad. If it genuinely refreshes you to do your duties better, it might be acceptable in measure. Aquinas even admits that some minor pleasures can be remedies for sorrow or fatigue – “a little wine for the heart” (cf. St. Paul to Timothy) – but warns that this is medicine, not to be abused. So ask: am I using this pleasure as a reasonable refreshment to better serve God, or as an escape and end in itself? The will’s inner language matters, as the dialogue example pointed out: “I permit this temporarily to restore order,” vs. “I deserve this pleasure.” The former is oriented by reason (virtue of eutrapelia – pleasant relaxation for the sake of renewed strength); the latter smacks of self-indulgence enthroning itself. Train yourself to always justify recreation in reference to higher goods, and it will stay moderate.
  (e) Time and mind-share: Does this activity or desire consume an excessive portion of my time, energy, or thoughts? Aquinas says one sign of inordinate passion is that it dominates one’s consciousness, “quietly expanding and displacing duties” (to paraphrase). If you find yourself daydreaming often about a certain pleasure, or organizing your whole day around it, that could indicate your lower appetite has grown too influential. For example, a person might spend hours curating their gourmet meals (time that could be spent on spiritual or family pursuits) – even if gluttony isn’t manifested in overeating, it appears as excessive solicitude for taste, which is disordered. The Thomistic ideal is “mode, species, and order” in all things: every legitimate good has its proper measure (mode), kind (species), and alignment (order) in the whole of life. Sin distorts these – either by excess, defect, or out-of-place pursuit. So examine how much time and priority you give various pursuits. Some will be clearly overboard. Scale them back in favor of higher goods. It helps to concretely schedule one’s day with hierarchy: prayer and duties first, pleasures fit in appropriately. If a pleasure regularly demands prime hours to the detriment of prime obligations, it’s a tyrant, not a pastime.

After such analysis, you should have a sense of “what is my A, B, C, D” as the conversation put it – meaning, what’s the worst attachment (A) down to relatively benign (D). Perhaps you identify, say, immoderate YouTube bingeing as A (most damaging to prayer, hardest to stop), overeating as B, vanity in clothing as C, and coffee habit as D. Then you have a map of battle. The Thomist approach would then be, following prudence: tackle them in order, with strategy appropriate to each’s magnitude.

2. Strategies for Reordering Attachments (Ascetical Plan)

Aquinas did not write a “manual of ascetic techniques” per se, but one can infer approaches from his principles and from traditional practices consistent with them:

• Eliminate or greatly limit the gravely disordered attachment (your “A”). If it’s a mortal sin, it must cease at once – with confession and amendment (grace is paramount here). If it’s not mortal but seriously impeding your spiritual life, consider a decisive period of abstinence or removal. For instance, a 3-month break from social media, a strict diet, or a dating fast, depending on what the issue is. This is akin to a spiritual “detox”. Aquinas notes that sometimes complete withdrawal is needed to restore health (just as a wound must first be cleaned and rested). You might need external accountability or altered circumstances to succeed (e.g. install internet filters, avoid keeping sweets at home, etc.). Aim to restore freedom: you want to reach the point where your will can say “no” peacefully. This often involves enduring a period of inner rebellion and discomfort – that’s the sensitive appetite protesting its lost dominance. Fortitude and temperance must be employed to endure this “sorrow of withdrawal”, which Aquinas would see as medicinal pain (like the sadness of penance which leads to joy of freedom). Encourage yourself with reasons: remind your intellect of why you undertake this (the goods that will result). Prayer is essential – ask God for strength at moments of weakness. Also, replace the lost indulgence with higher activities: e.g. fill leisure with reading, nature walks, more prayer, friendship – otherwise the void might beckon you back to the old habit (nature abhors a vacuum).
• Manage lesser attachments (“B” and “C”) in a stepwise way. The earlier conversation described “substitutionary detachment”: using a less intense pleasure to step down from a more intense one. This can be valid if done with the right intention. For example, if someone is quitting alcohol (A), they might allow themselves more coffee or dessert temporarily (B) to cope – provided the will’s direction remains to eventually curb B as well. Aquinas would likely counsel moderation even in that – but acknowledges convalescence may require some indulgence (like consolement in sorrow). The critical point, as the dialogue stressed, is the direction of the will: using a secondary pleasure as medicine, not as a new attachment. Signs of doing it right: you set clear limits (I’ll do this only for a month; I won’t exceed X amount; it won’t replace prayer). If those limits hold, fine. If you start “enjoying the descent” too much, it’s a red flag – you may just be shifting attachment, not truly detaching. So be honest: maybe you allow a small square of chocolate each time you resist pornography – if that helps break the bigger sin, okay for a time. But if you find you’re now gluttonously devouring chocolate and skipping virtue, the plan corrupted. The Thomistic tradition values ascetical prudence, the ability to calibrate penitential practices to the person’s capacity and growth. It’s better to make gradual sustainable changes than grandiose resolutions that collapse. However, one must guard against rationalizing endless delays. Set non-negotiable points: e.g. “I’ll allow myself 1 soda a day while quitting smoking, but after 2 months, I go to 0 sodas.” And stick to it. Use each success as momentum (virtue grows by acts, each victory makes next easier). Also, skip steps if possible: sometimes you can drop B sooner than thought and be free – don’t cling to crutches unnecessarily.
• Address root causes and higher-order solutions: Thomists always look at the causes of sin (via the seven deadly sins, etc.). Perhaps your attachment to comfort is exacerbated by an underlying sloth (sadness about spiritual effort). The cure for sloth is enkindling devotion and hope – e.g. reading lives of saints to inspire zeal. Or an attachment to human respect (vanity) might be cured by cultivating humility and the fear of God as greater than fear of men (meditate on God’s judgment vs. fleeting human praise). Identify if any of the capital vices (pride, avarice, lust, envy, gluttony, anger, sloth) are a driving “queen” in your soul causing other problems. Then target that queen with its opposing virtues and specific tactics. For instance, for pride: embrace hidden acts of service, practice obedience or consultation. For envy: deliberately praise others, practice gratitude for what you have. Each vice has an antidote regimen. Aquinas often gives such remedies in his moral questions (e.g. remedies for gluttony: think of health, the shame of being enslaved to belly, Christ’s example of fasting, etc.). In analysis, always connect the surface habit to the deeper disordered love that might be behind it. Then correct that love by contemplating the true good it should aim at. Much of asceticism is about changing your love – as Augustine says, “by loving the better, you expel love of the lesser”. So increase love for God (through prayer, sacraments, theological study) and love for neighbor (through acts of charity) – the more these burn, the easier the old flames die down.
• Use reason actively at temptation moments: Aquinas says reason can “incite or check the affections” by focusing on certain thoughts. So prepare rational weapons: short arguments or phrases to recall when passion flares. E.g. when lust tempts: “This pleasure is brief, the remorse long; I will not trade eternal joy for this”. Or for anger: “Soft answer turns away wrath – my dignity is in self-control, not in shouting.” These are like mini-syllogisms particular reason can throw at the sensitive appetite. They won’t always fully calm you, but they can weaken the passion enough to gain time and refuse consent. Another rational tactic: mental contrast – envision the aftertaste of indulging vs. the peace after resisting. Aquinas notes that a passion unfettered “carries a promise of delight” but often delivers sorrow (e.g. “the wicked man feels pain at having been pleased”). Remember past bitter experiences to dissuade present temptation.
• Keep the will directed to God (intention purity): Frequently renew your overall end: “Lord, I want to order my life to You. I intend this action for Your glory.” Aquinas says a good intention can’t make a bad act good, but it gives drive to pursue all the intermediate means. If your north star is “I seek God above all”, then skipping a secondary pleasure doesn’t feel like “losing happiness” but rather choosing a greater happiness. Work on making that conscious at decision points: “I choose the higher good here.” Over time, the will finds joy in sacrificing out of love (this is when virtue is really developed).
• Foster contrary passions to uproot wrong ones: Aquinas interestingly points out that one passion can counter another. Use this wisely. E.g. if sloth (aversion to effort) strikes, stir up shame or indignation in yourself: “Will I be a slave to the couch? No, I refuse!” That irascible kick (anger at your lower self) can overcome the concupiscible love of comfort. Or if lust draws you, consciously recall fear of God’s judgment or disease or loss of reputation – a bit of holy fear (irascible) can check concupiscence. If you are overly angry, recall the gentleness of Christ or the kindness someone showed you – awakening tenderness or contrition can dissolve anger. In other words, fight fire with fire: use one emotion to drive out another, aligning with reason’s judgment of what emotion is appropriate. This harmonizes with Ignatian and other spiritual traditions which say, for instance, if tempted to pride, deliberately meditate on your sinfulness to evoke sorrow; if tempted to despair, meditate on God’s love to evoke hope, etc.
• Be patient and persevere: Aquinas reminds that repeated acts form habits. So every small victory is laying a brick in the edifice of virtue. Conversely, occasional falls don’t demolish all progress – but they do wound, so treat them seriously (with contrition, confession if grave, and analysis of what went wrong). Avoid discouragement (a trick of the enemy to drive you back to sin out of frustration). Instead, use Aquinas’s realistic hope: “Virtue is generated gradually. The more vigorously one resists vice, the stronger the next resistance will be.” Even if you fail 30% of the time now, if you keep fighting, it may drop to 10%, then 0. And even that 0 must be maintained by vigilance. Virtue is a stable habit, but in via (in this life) we must contend with ongoing weakness – yet each virtue makes the next easier, and divine support increases as we grow in charity (God entrusts more help to the faithful steward). So never give up the fight – as long as the will wants to reorder the soul, progress is happening, albeit with ups and downs. Thomas would likely agree with the saying: “The only real failure is to stop trying.”

3. Monitoring Progress and Unknown Unknowns

A Thomistic mind values honesty with oneself. One must periodically review: Am I truly better ordered than before? Signs of genuine progress include: more promptness in doing good, less inner turmoil when denying yourself, more moderate emotional swings, and above all a deeper joy and peace in God. Aquinas says the virtuous person experiences a “connatural joy” in good acts. So if virtue is growing, your prayer or charity duties that once were hard will start to feel satisfying, even pleasurable in a higher sense. On the contrary, if you find virtue still burdensome and sin still sweet, you know much remains to be done (likely needing deeper conversion of will/heart, not just external control).

Be aware of self-deception: the conversation example gave subtle indicators of relapse vs. genuine controlled descent. Always question your motives: “Am I finding excuses to indulge, or truly using a thing moderately for a higher purpose?” The will is tricky; original sin gives us concupiscence of the eyes (curiosity, greed) and pride of life that can hijack intentions. One method Aquinas might advise is have a spiritual director or friend who knows your plan, to provide objective feedback. We see this in religious life – a superior assigns penances to avoid self-will creeping in. For laity, confessor or accountability partner could help.

Unknown unknowns: We all have blind spots – parts of our soul out of order we don’t even realize. The remedy is twofold: (a) prayer for light – “Search me, O God, and know my heart… see if there be any grievous way in me” (Ps 139). God often reveals deeper layers once we handle the obvious ones. Many saints testify that after conquering external faults, they became aware of subtler internal ones (like subtle pride or lack of trust). So expect that as you purify one area, another challenge may surface. (b) Study and learn from spiritual writers – Aquinas encourages learning wisdom from church teaching and wise persons. Reading about the seven deadly sins, or spiritual classics (e.g. The Imitation of Christ, John of the Cross, etc.), can uncover attitudes you didn’t question. For instance, perhaps you never considered that immoderate sadness at life’s trials can be a lack of fortitude or trust (a form of sloth or impatience). Or you may realize you engage in a lot of vain speech (talking too much about yourself), which is an imperfection related to pride. Little by little, let God’s truth shine into more corners, and apply the same Thomistic principle: identify the disordered tendency, oppose it with reason and virtue, fueled by grace.

Peace as the fruit of order: Aquinas writes that peace is the “tranquility of order” – when we are ordered under God, we have peace with Him, with ourselves, and with others. So the ultimate litmus test is that inner peace increases. Not a superficial peace (we might still have external troubles or hard responsibilities), but an interior unification and calm confidence in God. This is a great motivator: unlike sinful pleasures which give a quick thrill then unrest, virtue often is hard at first but yields a lasting serenity. Aquinas would attribute that to the will finally resting in the proper good (like a weight settling into its natural place). So if you glimpse that growing peace – cherish it and let it reinforce your resolve never to return to the old chaos.

In conclusion, the Thomistic understanding of the soul provides a comprehensive map: it shows every human capability and its role, identifies the distortions that sin introduces, and prescribes the virtues and practices to restore right order. It gives us a technical vocabulary (intellect, will, concupiscible, irascible, passions by name, etc.) which acts as tools for analyzing ourselves clearly. It offers a taxonomy of concepts and models: from the metaphysical (soul as form; powers distinguished by objects) to the moral psychological (11 passions, 7 vices, 4 wounds, 4 cardinal virtues). With this toolkit, one can systematically approach personal growth: it’s not a random emotional journey but a rational quest guided by objective truth about human nature. The “unknown unknowns” become fewer as we shine the light of this wisdom into our interior, naming things rightly and addressing them rightly.

The ultimate goal is to fulfill the greatest commandment: to love the Lord your God with all your heart, soul, mind, and strength, and your neighbor as yourself. Thomistic spirituality shows that this is achieved when each part of the soul contributes to that love: the intellect contemplates God’s truth, the will chooses His will, the irascible fights for God’s honor and the arduous good of holiness, the concupiscible finds holy delight in God and in virtuous joys, and the body itself becomes a living sacrifice, an instrument of charity. In that state, man truly lives the life of grace – already a foretaste of the perfect order (and bliss) of heaven, where nothing in us resists the Divine Good. Aquinas himself lived this harmony; at the end he said “All that I have written is straw” compared to the reality of God he glimpsed. This humility and union show a soul completely ordered to God.

While most of us are far from that, we now have a manual of the soul’s workings and remedies to guide our ascent. By steadily applying these Thomistic principles – clear knowledge of the soul, cultivation of virtue, rational reflection, and reliance on God’s grace – we can hope to become “master of our soul” in the true sense: not by domination, but by integration under the true Master, God. The human soul fully alive in virtue is, as Aquinas would agree, a masterpiece of God’s creation: “The virtuous man is a microcosm of order, reflecting God’s wisdom and goodness”.

Conclusion

The human soul is a real, structured principle with distinct powers, an internal hierarchy, and a knowable order, rather than as a vague inner sentiment or mere psychological abstraction. In the Thomistic framework, moral struggle and spiritual growth are intelligible because disorder is identifiable, governance is possible, and virtue has a precise function: to restore harmony by subjecting lower powers to higher ones under reason and will. This understanding replaces confusion with diagnosis and moralism with strategy, giving the reader a technical grammar for self-knowledge, self-governance, and ascetical discernment. What remains is not further theory but application: to use this framework to examine one’s own interior life, locate misalignment, cultivate the appropriate virtues, and steadily reorder the soul.

May this knowledge serve to aid your journey to sanctity.

Special thanks to my great friend ChatGPT.