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Aquinas - Selected Philosophical Writings (Oxford)


St Thomas Aquinas (1225-74), a Dominican friar, was the greatest of the Western European medieval philosopher-theologians, and a leading figure in the thirteenth-century resurgence in Aristotelian studies. (Aquinas - Selected Philosophical Writings (Oxford) p.0)

In 1225 Thomas was born at Roccasecca, near Aquino, the youngest son of an impoverished landowner of Lombard extraction and a woman with Norman blood in veins. His father was vassal to Frederick II, king of Sicily, Holy Roman Emperor. (Aquinas - Selected Philosophical Writings (Oxford) p.xiii)

From the age of 5, Thomas was brought up in the school of the Benedictine monastery of Monte Cassino, amid a life of manual labor, prayer, scriptural reading, and meditation, and possibly he was intended to spend the rest of his life there, perhaps to become abbot of the place. But the fighting between Frederick and the Pope brought the emperor’s troops into the monastery in 1239, and the 14-years-old was sent on to the University of Naples. Here the course of his life totally changed. (Aquinas - Selected Philosophical Writings (Oxford) p.xiii)

Much ink has been spilled on the question of whether he is a theologian or a philosopher; I think it is like discussing whether somebody is a cyclist or a pedestrian! Most people have both skills and use whichever is the more appropriate in the context. (Aquinas - Selected Philosophical Writings (Oxford) p.xxxi)


Many of the issues he discusses are still alive today: Is there order in the world, and does the reveal the transcendent presence of a God? Have we words to talk about him? Is he active even in chance events and freely willed action? How can the mind and body of human beings be one? What role do theories of virtue and natural law play in ethics? (Aquinas - Selected Philosophical Writings (Oxford) p.0)

The initial section (in italics) is a reference. “It seems”, “But against that”, In reply” and “Hence”. “It seems” and “But against that”, and then answered by a thrice-repeated “In reply” and “Hence”. (Aquinas - Selected Philosophical Writings (Oxford) p.1)

Inside the mind

How does it work?
Human reason as such isn’t measured of things, but certain principles imprinted in it provide a general standard of measurement for everything human beings do since our natural reason can lay down standards for such things even if it can’t lay down standards for the products of nature. (Aquinas - Selected Philosophical Writings (Oxford) p.421)

The usage of reason
So from all that has been said we can gather that in its first sense using reason characterizes logic, in its second ethics, and in its third natural science. (Aquinas - Selected Philosophical Writings (Oxford) p.35)

The end of reason is intelligence
Clearly then reason when analyzing ends in intelligence, simplifying many things into a single truth, and when synthesizing and discovering begins from intelligence, where many things are comprehended in one. (Aquinas - Selected Philosophical Writings (Oxford) p.35)

It differs from animals
So instead of such equipment, human beings must use the reason they have to devise for themselves external substitutes for what in other animals is intrinsic. (Aquinas - Selected Philosophical Writings (Oxford) p.87)

Sexy Reason
Now reason rules sensuality in the way soul rules body. (Aquinas - Selected Philosophical Writings (Oxford) p.404)

What is intelligence?
So there is no alternative: only one thing that is its own existence can exist, and all other things must have an existence differing from their whatness or nature or form. Intelligence then must have existed over and above their form; and that explains the saying: intelligence is what has form and existence. (Aquinas - Selected Philosophical Writings (Oxford) p.104)

The range of intelligence 
And so intelligence is described in the book of Causes as unlimited below but limited above: limited in existence which they acquire from above, but unlimited below since their forms are not limited to what some acquiring material can take on. (Aquinas - Selected Philosophical Writings (Oxford) p.107)

Where is truth?
Truth is a matching of thing and mind, but such matching can only exist in the mind. So truth too can only exist in the mind. (Aquinas - Selected Philosophical Writings (Oxford) p.56)
Aristotle says that good and bad are in things but truth and falsehood in the mind. (Aquinas - Selected Philosophical Writings (Oxford) p.57)

What is the truth?
What matches God’s mind is called true in the sense of fulfilling what God’s mind has laid down, as we see in the definitions of Anselm and Augustine and in the one quoted from Ibn Sina: the truth of a thing is the possession of the existing established for it. (Aquinas - Selected Philosophical Writings (Oxford) p.57)

How does it work?
¹The attributes of something are determined by it only when caused by it: light in the air, for example, because it is caused by the external sun, follows the sun’s movements rather than those of air. In the same way truth in the mind, because caused by things, isn’t determined by how the mind sees things but by how things are: for statements - and the understanding they embody- are called true or false inasmuch as things are or are not so... (Aquinas - Selected Philosophical Writings (Oxford) p.58)
Being true is a matching of things and understanding. (Aquinas - Selected Philosophical Writings (Oxford) p.58)
So the notion of truth is first found in understanding when understanding first starts to have something of its own which the external thing doesn’t have, yet which corresponds to the thing and can be expected to match it. (Aquinas - Selected Philosophical Writings (Oxford) p.59)
Clearly then being true applies first to the connections and disconnections made in understanding, secondarily to definitions of things that imply true or false connections, thirdly to things as matching God’s understanding or able to match human understanding, and fourthly to human beings choosing truth, or giving a true or false impression of themselves or others by what they say or do. (Aquinas - Selected Philosophical Writings (Oxford) p.59)

Things are desirable because:
We must also differentiate in a similar way the ability to desire that depends on our power of sense. This power divides into two: for things are desirable either because they themselves delight and suit the senses, and these require a capacity for affective emotion; or because they empower us to enjoy things delightful to the senses, though they in themselves sometimes sadden the senses, as when an animal fights to repel obstacles and gain access to what he naturally enjoys; and this requires a capacity for aggressive emotion. (Aquinas - Selected Philosophical Writings (Oxford) p.135)

The ability to desire
By nature understanding desire the understandable as something to understand, for it has a natural desire to understand as the senses have to sense. But we desire what can be sensed and understood not only for sensing and understanding but also for other reasons; so we must have an ability to desire over and above our abilities to sense and understand. (Aquinas - Selected Philosophical Writings (Oxford) p.136)

The bad desire  
Though human beings desire their goal by nature they don’t have by nature a desire for everything they need to attain that goal, but acquire that desire by reasoning, debating what they need, and making choices. Also, there’s nothing odd about desiring something hateful in itself as a means to an end, in the way we desire amputation of a limb for health’s sake. And this is the way death, which everyone flees from by nature, can be desired for the sake of bliss; as St Paul also says in the Philippines: I desire to be dissolved and live with Christ. (Aquinas - Selected Philosophical Writings (Oxford) p.326)

Happiness from philosophy
Moreover, the ultimate happiness of human beings, as philosophy sees it, consists in knowing the immaterial substances. For since happiness is whatever activity most fulfills us, it ought, as Aristotle suggests, to be concerned with the most perfect objects of intellect. Now the happiness of which philosophers talk is an activity deriving from wisdom since wisdom is the crowing strength and virtue of our most perfect ability, intellect, and that sort of activity is happiness, as Aristotle says. (Aquinas - Selected Philosophical Writings (Oxford) p.40)

Human Happiness
The happiness of human beings is twofold. There is imperfect happiness in this life which Aristotle is speaking, consisting in the contemplation of immaterial substances to which wisdom disposes of us, an imperfect contemplation such as is possible in this life, which does not know what such substances are. The other happiness is the perfect happiness of the next life when we will see the very substance of God himself and the other immaterial substances. But what brings that happiness won’t be any theoretical science, but the light of glory. (Aquinas - Selected Philosophical Writings (Oxford) p.50)
Species of feelings
So we see that there are three groupings of affections: loving and hating, desiring and aversion, feeling pleased and feeling sad; and three of aggressive feelings: hoping and despairing, feeling afraid and feeling bold, and feeling angry (which has no antithesis). That makes eleven distinct species of feeling - six affective and five aggressive- which comprise every animal feeling there is. (Aquinas - Selected Philosophical Writings (Oxford) p.169)

Passion leads to decomposition
Passion leads to decomposition, for Aristotle says, that as passion intensifies substance decays. But the soul can’t decompose. So it can’t be subject to passion. (Aquinas - Selected Philosophical Writings (Oxford) p.157)

Exchange for the worst
But here too a distinction should be made: exchange for the worse are more properly passions than exchanges for the better: feeling sad is more properly passion than feeling pleased. (Aquinas - Selected Philosophical Writings (Oxford) p.158)

How does it work?
Passion implies being drawn by some external agent, and this is most apparent when a thing is drawn away from some state congenial to it. (Aquinas - Selected Philosophical Writings (Oxford) p.157)

How it occurs
Now passions occur first in perception and then in desire since we can’t undergo desire until we have undergone perception. So passions are perceptions rather than desires. (Aquinas - Selected Philosophical Writings (Oxford) p.158)

Against that
Perception isn’t an attraction to something in its own reality, but awareness of it through some representation of it in the mind, innate or acquired depending on the type of mind. (...) So passions are desires rather than perceptions. (Aquinas - Selected Philosophical Writings (Oxford) p.159)

And that is why Hugh says that Love enters where knowledge is left outside. (Aquinas - Selected Philosophical Writings (Oxford) p.322)
Moreover will love moves us more ardently than mind’s knowledge since knowledge assimilates but love transforms, as pseudo-Dionysius says. So will is more able to be moved than the mind. If then mind can be compelled to move, a fortiori will. (Aquinas - Selected Philosophical Writings (Oxford) p.173)


How it works
Being angry is the heart’s blood boiling. So clearly acts of sense-desire are more truly passions than acts of sense-perception, even though both are acts of bodily organs. (Aquinas - Selected Philosophical Writings (Oxford) p.160)

Anger without the weakness of feelings
Thus Augustine: The holy angels punish but without feeling anger, and help us without feeling compassion. But our ordinary human language applies these passion-words to them too, because what they do is similar though without the weakness of feelings. (Aquinas - Selected Philosophical Writings (Oxford) p.161)

Anger has no antithesis
Anger is peculiar in being the only feeling that can’t have an antithesis, whether on the model of approach- recoil, or due to the antithesis of good and bad. For anger is provoked by evils already done to us and hard repel. Either we yield to such evils sadly (an affective feeling) or we are impelled to confront the harm done us angrily. But no feeling can impel us to avoid the evil, since the evil is already present or past. (Aquinas - Selected Philosophical Writings (Oxford) p.166)
Once a good is achieved the only movement remaining is resting of desire in the achieved good, that is to say, its effective enjoyment. So the movement of anger can’t have any antithetic movement, but simply an absence of movement: as Aristotle says the only opposite to being angry is calming down, which is not its antithesis but its absence or lack. (Aquinas - Selected Philosophical Writings (Oxford) p.167)

Joy & sadness

For Aristotle says feelings are accompanied by joy or sadness. But joy and sadness are effective in nature. So all feeling is effective in nature, and there is no distinction between affective and aggressive feelings. (Aquinas - Selected Philosophical Writings (Oxford) p.162)

What is Good and bad feeling? 
So any straightforward feeling for good or bad as such is an affective feeling, like feeling joyful or sad, loving or hating, or the like; and any feeling for good or bad as something challenging, the attaining or avoiding of which will require effort, is an aggressive feeling, like feeling bold or afraid or hopeful, and the like. (Aquinas - Selected Philosophical Writings (Oxford) p.163)

Difference between effective and aggressive feelings
As pleasurable the good attracts our affections, and as hard to attain it repels them, so we had to have another ability called our aggressive ability, enabling us to pursue such good and avoid such bad. So effective and aggressive feelings differ in kind. (Aquinas - Selected Philosophical Writings (Oxford) p.164)

How good and bad feelings work
Now in the movement of appetite good attracts and bad repels. So good first provokes an inclination or bias or affinity to itself, called loving (having an antithetic movement, hating,  in regard to evil); then secondly, if the good is not yet possessed it provokes a movement towards getting it, called desiring (opposed to aversion or disgust, as regards evil); and thirdly, when the good is finally achieved,, it provokes a repose of desire in the good achieved, called feeling pleased or enjoyment (and opposed to pain or feeling sad, as regards evil). And aggressive feelings presuppose than same bias or inclination towards seeking good and avoiding evil that underlies effective feeling directed straightforwardly at good and evil. And if the good is not yet acquired this provokes hope or despair and if the evil is not yet upon us fear or boldness. But good acquired provokes no aggressive feeling because, as we have said, it no longer offers a challenge; while evil already upon us provokes anger. (Aquinas - Selected Philosophical Writings (Oxford) p.168)

Antithetic states

What are they
Now Aristotle distinguishes tow sorts of the antithesis between moving towards or away from one state, as in changes of substance where birth moves to existence and death move away; and sometimes the antithesis is between movements that lead words antithetic states, as in changes of quality where getting whiter moves from black to white and getting blacker moves from white to black. (Aquinas - Selected Philosophical Writings (Oxford) p.165)

Antithetic with feelings
Moreover, Ibn Sina says that every emotion approaches or retreats. Now the approach is an attraction to good, and retreat is repulsion from bad; for just as Aristotle says that good is what everyone desires, so bad is what everyone recoils from. So all antitheses between animal passions must be between good and bad. (Aquinas - Selected Philosophical Writings (Oxford) p.164)
Every feeling is either affective or aggressive, as we have said, and each of these has its own kinds of antithesis. So every feeling has an antithetic feeling. (Aquinas - Selected Philosophical Writings (Oxford) p.166)

The differences of feeling are made through antithesis 
Since every emotion is an approach to or a recoil from good or bad, differentiation of emotions must come either from the difference between good and bad, or from that between approach and recoil, or from that between more or less approach and recoil. Now the first two differences do introduce antitheses between feelings, as we have seen; whilst the third doesn’t differentiate kinds of feelings, for then there would be unlimited species of feeling. So one can’t differentiate species of feeling within a genus except by antithesis. (Aquinas - Selected Philosophical Writings (Oxford) p.167)

Passion for animals 
For animals, passions are differentiated by the object. Now the objects of passions are good and bad and they differentiate passions by antithesis. So unless the feelings within each division of feeling are antithetic they will not differ in kind. (Aquinas - Selected Philosophical Writings (Oxford) p.167)


What is Will
There is a desire for good in everything: good, the philosophers tell us, is what all desire. In things without awareness this desire is called natural desire: the attraction a stone has for downwards, for instance. In things with sense-awareness, it is called animal desire and divides into capabilities of affective and aggressive feelings. In things with understanding, it is called intellectual or rational desire: will. So created intellectual substances have wills... (Aquinas - Selected Philosophical Writings (Oxford) p.169)

What is the will for humans? 
Will is a desire of reason in the sense of following reason: its activity belongs at the same level of ability in the soul but is not of the same sort. And the same is true of aggressive or effective feelings and the senses. (Aquinas - Selected Philosophical Writings (Oxford) p.136)
Bur the understood form by which intellectual substances are active issues from the intellect itself, as something conceived and in a sense thought up by itself: as we see in the forms that craftsmen conceive and think up and operate according to. So intellectual substances move themselves to activity and are masters of their own actions. They, therefore, have wills... (Aquinas - Selected Philosophical Writings (Oxford) p.170)

What is ill for substance with a lack of awareness 
Moreover, things lack the freedom to decide either because they lack all judgment, like stones and plants which lack awareness, or because their judgments are fixed by nature, like non-reasoning animals. (Aquinas - Selected Philosophical Writings (Oxford) p.170)

Will is a passive ability
Now will object acts on it, for Aristotle says that what we desire moves but is not moved, whereas our desire moves and is moved. So will is a passive ability, and the activity of willing a being affected. (Aquinas - Selected Philosophical Writings (Oxford) p.172)

With no Will, there is no Ethics
The opinion is also philosophically anarchic, not only opposed to the faith but destroying the foundation of ethics. For if we are not in any way free to will but compelled, everything that makes up ethics vanishes: pondering action, exhorting, commanding, punishing, praising, condemning. (Aquinas - Selected Philosophical Writings (Oxford) p.176)

Will and Action
Firstly that like other things human beings originate actions. The active or motive principle peculiar to them is, as Aristotle says, mind and will, which is partly like the active principles in nature and partly unlike. (Aquinas - Selected Philosophical Writings (Oxford) p.176)

How does will work
For this is the way in which will puts itself and all other abilities to work: I think because I want to, I use all my other abilities and disposition because I want to, so that Ibn Rushd defines a disposition as what is ready to be used when wanted. If then we are going to show that will is not compelled to act, we must consider acts of will both as to their exercise and as to their determination by some object. (Aquinas - Selected Philosophical Writings (Oxford) p.177)

Where does the movement start?
¹¹¹ We are forced to admit that, in any will that is not always willing, the very first movement to the will must come from outside, stimulating the will to start willingly. (Aquinas - Selected Philosophical Writings (Oxford) p.178)

Will disposition 
 ¹¹² Because of some disposition in the one willing since, as Aristotle says, what you want depends on what you are. The will of an angry man won’t agree with that of a peaceable one; the same thing is not appropriate to both, just as the same food won’t appeal to the sick and the healthy. (Aquinas - Selected Philosophical Writings (Oxford) p.179)
¹¹³ Mind, for example, by actually knowing premisses actualizes its own potentiality for knowing conclusions: and will by willing a goal actualizes its own potentiality for willing means. (Aquinas - Selected Philosophical Writings (Oxford) p.183)

Act of will
¹¹⁴ But the defect is not a moral fault, for reason can consider this good or that good or nothing at all without any fault until the moment comes when the will tends towards the undue goal; and then we already have an act of will. (Aquinas - Selected Philosophical Writings (Oxford) p.289)

¹³² Choosing involves two things: intending a goal (the role of the moral virtue) and picking out the means (the role of prudence), as Aristotle says. When emotion is in question, the right intending of a goal needs our aggressive and affective urges to be disposed to good. So the moral virtues concerned with emotion must dispose of those urges, while prudence disposes of our reason. (Aquinas - Selected Philosophical Writings (Oxford) p.406)


The action
Aristotle says that virtuous people act as they should when they should, and in accordance with the other circumstances. So non-virtuous people must do the opposite, acting, according to various vices, when they shouldn’t, or where they shouldn’t, or disregarding some other circumstances. A human action then can be good or bad because of some circumstances. (Aquinas - Selected Philosophical Writings (Oxford) p.346
Moreover, Augustine says that virtue is the good use of our freedom to choose. But using free choice is an activity. So virtue is action, not disposition. (Aquinas - Selected Philosophical Writings (Oxford) p.391)

Virtue is in choice 
Good use of our freedom to choose is said to be a virtue in the same sort of way: because virtue is ordered to that as its own proper activity. For the activity of virtue is nothing else than good use of one’s freedom to choose. (Aquinas - Selected Philosophical Writings (Oxford) p.392)

The reason is the better that prevails in weakness 
Reason shows itself the more perfect, the better it can prevail over or tolerate weakness in our body and lower parts. So virtue, the works of reason, is made perfect in weakness, but not in a weakness of reason: rather in a weakness of our body and lower powers. (Aquinas - Selected Philosophical Writings (Oxford) p.395)

Virtue & mind
Moreover, Augustine says that the mind begins where there is something we don't share with the beasts. But Aristotle says there are certain virtues in the unreasoning parts of us as well. So not every virtue is a good quality of mind. (Aquinas - Selected Philosophical Writings (Oxford) p.396)

Where is virtue 
So virtue must exist not in the intellect but in our abilities to desire. (Aquinas - Selected Philosophical Writings (Oxford) p.401)

Intellect  & virtue 
A person isn’t good just because he has knowledge or know-how. So intellect is not the subject of virtues. (Aquinas - Selected Philosophical Writings (Oxford) p.402)

Charity is no virtue 
Virtue is concerned with the difficult, as Aristotle says. But charity isn’t concerned with the difficult; on the contrary, as Augustine says: All that is heavy and beyond bearing, love makes easy and next to nothing. So charity is no virtue. (Aquinas - Selected Philosophical Writings (Oxford) p.421)

Actions cannot always be good
Augustine says there are some things that can’t be done well, no matter how good the goal or the will. (Aquinas - Selected Philosophical Writings (Oxford) p.382)

Good and bad

Why should I be good?
So being good adds something real to exist. (Aquinas - Selected Philosophical Writings (Oxford) p.59)

The cause of evil 
So evil can’t be a cause of anything. If evil, then, has a cause, it must be caused by good. (Aquinas - Selected Philosophical Writings (Oxford) p.285)

The cause of good and bad actions
Hosea says: They have become as abominable as the things they have loved. Now human beings become abominable to God because of the bad they do. So their actions are bad because the objects they love are bad, and similarly for good actions. (Aquinas - Selected Philosophical Writings (Oxford) p.345)

The subjectivity of Good and Bad
Good actions can be done for bad ends - giving to the poor out of vanity - and bad actions for good ends - stealing to give to the poor. So an action’s goal doesn’t make it good or bad. (Aquinas - Selected Philosophical Writings (Oxford) p.347)

The cause of Good
The good person produces good from the store of good in his heart - reads: A person does as much good as he intends. But intentions don’t only make external doing good, but also our willingness, as we have said. So a person has as good a will as he intends. (Aquinas - Selected Philosophical Writings (Oxford) p.374)

How moral actions work
So the first source of movement in moral actions is what is perceived, the second the perceiving power executing reason’s command. Now the executive power’s action already presupposes moral goodness or badness, for external action is only thought moral if it is voluntary: so when will is good the external action is good, and when evil. If the external act was deficient with some non-voluntary defect there would be no moral evil there at all: limping, for example, isn’t a moral fault but a natural one, and such a defect in the executive power totally or partially excuses us from moral fault. (Aquinas - Selected Philosophical Writings (Oxford) p.287)


What is philosophy?
Augustine says, quoting Varro, what other reason is there for doing philosophy but to be happy. (Aquinas - Selected Philosophical Writings (Oxford) p.10)


The goal of human life
The goal of human life suppresses that of other animals even more than the one life surpasses the other, and what gives human life its greater excellence is precisely the greater excellence of the goal it is ordered to. So it doesn’t have to contain its ultimate goal in the way the lives of other animals do. (Aquinas - Selected Philosophical Writings (Oxford) p.326)

Life meaning
Life has two meanings: sometimes it means the living thing’s very existence and that has to do with the substance of the soul, which is the source of existence in living things; but it also means the living thing’s activity, and in this sense, virtue disposes us to live rightly, for it is a virtue that disposes us to act rightly. (Aquinas - Selected Philosophical Writings (Oxford) p.400)

Forms of life
Clearly then there are three levels among the power of the soul, or living abilities: those of vegetable life, of animal life, and of rational life. But there are five sorts of ability: namely, nutritive, sensitive, intellectual, appetitive, and locomotive, some of these containing several powers under them, as we have said. (Aquinas - Selected Philosophical Writings (Oxford) p.135)


What is existence?
And this is why pseudo-Dionysius says that though living things are more excellent than existent things, existence is more excellent than life: for living things don’t only have a life but, together with life, have existence. (Aquinas - Selected Philosophical Writings (Oxford) p.208)

It comes from nothing 
So it is impossible for something to come to be from nothing. (Aquinas - Selected Philosophical Writings (Oxford) p.253)


In this way, then, it is clear how essence is realized in substances- composite and simple - and their incidental properties, and how logical concepts of generality arise in all except the first supremely simple [being], whose simpleness refuses to be placed in either genus or species, and cannot, therefore, be defined, in whom may this discourse have its end and its fulfillment. Amen. (Aquinas - Selected Philosophical Writings (Oxford) p.113)


What they are? 
Clearly then Socrates' essence differs from human essence only by being demarcated. Socrates, as Ibn Rushd says, is nothing more than animality plus rationality; those are what he is. (Aquinas - Selected Philosophical Writings (Oxford) p.94)

Against that 
For it, commonness was part of what we understood by a human, then wherever humanness was found commonness would be found too, which is false: for we don’t find commonness in Socrates but everything in him is individuated. (Aquinas - Selected Philosophical Writings (Oxford) p.100)


What is the soul?
So our conclusion is that soul is itself a thing in the sense of being able to subsist by itself, but one which does not possess a complete specific nature of its own; rather it is something which completes a human being’s specific nature by being the form of a human body. So that the soul is at once and the same time a form and itself a thing. (Aquinas - Selected Philosophical Writings (Oxford) p.189)

Now the soul is by essence immaterial, so by essence intellectual. Intellect then is its essence, and other abilities likewise. (Aquinas - Selected Philosophical Writings (Oxford) p.124)

Reasoning soul
And it is a fortiori impossible for the life-principles of things which reason, the activities of which involve abstracting the species of things not only from matter but from every material condition of particularity, so as to know them in general. And there is something further still to consider, which is peculiar to erasing souls: not only do they take in species that can be understood without their matter and material condition, but, as Aristotle proves, they cannot shares that special activity of theirs with any bodily organ, in the sense of having a bold organ for thinking as an eye is a bodily organ for seeing. (Aquinas - Selected Philosophical Writings (Oxford) p.187)

Soul & Mind
Thus Aristotle says that the mind is a sort of indecomposable substance. And Plato’s saying that soul is immortal and subsists of itself because it moves amounts to the same. For he is using movement broadly to mean any activity, and the mind moving must be interpreted to mean that it is active of itself. (Aquinas - Selected Philosophical Writings (Oxford) p.188)


Where it belongs
In this respect change belongs to the categories of action and passion; for these two categories derive from the notions of agents cause and effect, as we have seen. (Aquinas - Selected Philosophical Writings (Oxford) p.90)

The actualization of change 
More clearly than change actualizes the potentialities of both agent and patient. And that also can be said in particular building actualizes both builder and what he builds as such. And the same with healing, and other changes. (Aquinas - Selected Philosophical Writings (Oxford) p.90)


Why have laws?
Law is a standard of measurement for behavior, fostering certain actions and discouraging other; for law derives from binding, since binds one to act. (Aquinas - Selected Philosophical Writings (Oxford) p.411)

How does the law come into being?
Since the law is a standard of measurement, there are two ways it exists in things. Firstly, in what does the measuring and regulating, and since that is the proper role of reason, the law in this sense exists in reason alone. Secondly, in what is measured and regulated, and law in this sense exists in everything which tends towards something in obedience to the law. (Aquinas - Selected Philosophical Writings (Oxford) p.411)
Cicero told us: law starts with what nature produces, then by use of reason certain things become customs, and finally things produced by nature and tested by customs are sanctified with the awe and religious weight of laws. (Aquinas - Selected Philosophical Writings (Oxford) p.420)

Principles of Nature

Principles of life
Now certain people deny to the soul or life-principles of human beings both of these requisites for being itself a thing, saying the principle of life is equilibrium (Empedocles) or complexity (Galen) or something similar. In this case, the life principle could neither subsist in its own right nor be a whole instance of some species or genus of substance, but would simply be a form of matter like all others. Yet this is already impossible for the life-principles of plants, the activities of which - like digestion and growth - must spring from a source transcending the physical-chemical reactions those activities employ as tools, as Aristotle shows. (Aquinas - Selected Philosophical Writings (Oxford) p.183)

Principles of life Of Humans 
And so the life-principle of a thing with understanding has to act on its own, with an activity peculiar to itself not shared with the body. And because activity flows from actuality, the understanding soul must possess an existence in and of itself, not dependent on the body. (Aquinas - Selected Philosophical Writings (Oxford) p.188)

Which are they?
So there are three principles [or origins] of nature: matter, form, and lack of form; one, namely form, is where generation is going to, and the other two characterize where generation comes from. (Aquinas - Selected Philosophical Writings (Oxford) p.69)
Thus, matter, form, and lack of form, or potentiality and actuality, are the principles of all the categories- substance and the rest - but the matter of substance and of quantity, and their form and lack of form differ in genus and agree only proportionately: as the matter of quantity to quantity. However, the substance is also the cause of the other categories, so that substance’s principles are also principles for every other category. (Aquinas - Selected Philosophical Writings (Oxford) p.82)

The need for generation
So now we have shown nature to have three principles: matter, form, and lack of form; but these are still not enough for the generation to occur. For what potentially exists can’t bring itself to actualization: copper is potentially a statue, but can’t make itself into a statue: it needs a workman to draw the statue’s form out of potentiality into actuality. (Aquinas - Selected Philosophical Writings (Oxford) p.71)

Generation and natural deliberation
And since [the guitar player] who acts by will is more likely to deliberate than things that act by nature, we can argue a fortiori that natural agents can tend to goals without deliberating, were tending towards is simply having a natural bias towards something. (Aquinas - Selected Philosophical Writings (Oxford) p.72)

Kinds of causes 
Now there are four kinds of causes. Two of these - matter and form - are parts of the thing, of its essence; so any inscription to a subject made on their account will fall into the category that ascribes substance: as when we say that human beings are rational or have bodies. And goals don’t cause except through agents, for a goal counts as a cause in so far as it moves an agent. So we are left with agents as the only causes which can give rise to the qualification of a subject by something outside. (Aquinas - Selected Philosophical Writings (Oxford) p.87)

Potentiality & Actuality

What are they?
A thing’s power or potential is its openness to some act or actuality, either the primary act of having the form or the second act of action. (Aquinas - Selected Philosophical Writings (Oxford) p.65)

Nevertheless, one ability can sometimes turn out to be a root or source of others, the actualizations of those others presupposing the actualization of the first power. This is the way our ability to feed is the root of our abilities to grow and to reproduce, both of which utilize food; and it is in this way too that our common root sensitivity is the root of our imagination and memory, which presuppose the actualization of common sense. (Aquinas - Selected Philosophical Writings (Oxford) p.143)

The active power 
Moreover, Augustine and Aristotle say acting is a more excellent thing than being acted on. Now the lowest-level powers of living things-vegetative powers- are all active powers. So a fortiori the highest-level power of living things- understanding- must be active. (Aquinas - Selected Philosophical Writings (Oxford) p.145)


Complete science 
We know that science must treat the beginnings of its subject-matter since as Aristotle makes clear, science is incomplete unless it knows its own beginnings. (Aquinas - Selected Philosophical Writings (Oxford) p.27)

For an element is what things are ultimately made of, existing in the things and indivisible in its own nature; but if the substance of the elements has disappeared the compound is no longer made up of indivisible things existing in it. (Aquinas - Selected Philosophical Writings (Oxford) p.118)


What is Eternity
According to Aristotle the present moment of time persists unchanged throughout time. But the nature of eternity seems to consist precisely in remaining unbrokenly the same throughout the whole course of time. Eternity then must be the present moment of time. But the present moment of time is in substance identical with time itself. So eternity must be in substance identical with time. (Aquinas - Selected Philosophical Writings (Oxford) p.212)

What is the present time? 
The present moment persistently underlies time, altering state continuously; just as time corresponds to movement [of the heavens], the present corresponds to what moves, which remains in substance the same throughout time though it alters its position, first here then there, and, by altering its position, moves. Time consists of the passing of the present moment as its alters state. Eternity, however, remains unchanged both in substance and in state, and thus differs from the present of time. (Aquinas - Selected Philosophical Writings (Oxford) p.213)

The beginning and end of time 
Every moment passes but not all pass from one state to another: the last moment of time passes only from a state, and the first moment only into one... (Aquinas - Selected Philosophical Writings (Oxford) p.269)

Against that 
¹⁴⁰ But against that: what differentiates the temporal present from the eternal present is that it passes. But what passes from one state to another. So all moments must pass from an earlier to a later state. So there can’t be either a first moment or a last... (Aquinas - Selected Philosophical Writings (Oxford) p.264)

Time, cleverness, and limit 
Moreover, Priscian tells us that as time goes by people get clever. But since cleverness isn’t limitless, the time during which cleverness has been growing can’t be limitless either; nor can the world. (Aquinas - Selected Philosophical Writings (Oxford) p.265)

How God perceives Time 
A convenient illustration may be drawn from space, since, according to Aristotle, the successiveness of time derives from that of change and movement, and that from extended successiveness in space. So if we imagine many people traveling a road, all those traveling will have knowledge of the people in front and behind them, according to their beforeness and afterness in space. And so each traveller will see the people next to him and the people in front, but not the people behind. But id someone is outside the whole traveling situation, standing in some high tower, for example, from which he can see the whole road, then he will have a bird’s-eye view of every traveler, not seeing them as in front or behind in relation to his own seeing, but seeing them all together in front and behind each other. Now since our knowledge occurs within time, either in itself or incidentally (so that when making propositional connections and disconnections we have to add tense, as Aristotle points out), things are known as present or past or future. Present events are known as actually existing and perceptible to the senses in some way; past events are remembered, and future events are not known in themselves- because they don’t yet exist - but can be predicted from their causes. (Aquinas - Selected Philosophical Writings (Oxford) p.282)


Exodus 3 represents God as saying: I am who am. (Aquinas - Selected Philosophical Writings (Oxford) p.199)

God’s existence

How is the existence of God
The acme of perfection in life, then, belongs to God, in whom to exist is to understand... So that in God the idea in his mind is what God himself is. (Aquinas - Selected Philosophical Writings (Oxford) p.116)

A critic of God’s existence
It seems there is no God: For if one of two mutually exclusive things were to exist unbounded, the other would be totally destroyed. But the word God implies some unbounded good. So if God existed, no evil would ever be encountered. Evil is, however, encountered in the wild. So God does not exist. (Aquinas - Selected Philosophical Writings (Oxford) p.199)

A defense on gods existence
There are five ways of proving there is a God: (...) we are forced eventually to come to the first cause of change, not itself being changed by anything, and this is what everyone understands by God. (...) We are forced to postulate some first agent cause, to which everyone gives the name God. (...) We are forced to postulate something which of itself must be, owing to this to nothing outside itself, but being itself the cause that other things must be. (...) So everything in nature is directed to its goal by someone with understanding, and this we call God. (Aquinas - Selected Philosophical Writings (Oxford) p.201)
It seems self-evident that God exists: For things of which we are innately aware - first principles, for instance- are said to be self-evident to us. But, as John Damascene says, the awareness that God exists is implanted by nature in everyone. So it is self-evident that God exists. (Aquinas - Selected Philosophical Writings (Oxford) p.196)

Gods existence proven through his effect
Only effects commensurate with their cause can give comprehensive knowledge of it, but, as we have said, any effect whatever can make it clear that the cause exists. God’s effects then are enough to prove that God exists, even if they are not enough to help us comprehend what he is. (Aquinas - Selected Philosophical Writings (Oxford) p.199)

The presence of God
God then causes everything’s activity inasmuch as he gives the power to act, maintains it in existence, applies it to its activity, and inasmuch as it is by his power that every other power acts. And when we add to this that God is his own power and therefore exists within everything, not as a part of its being but as holding it in existence, it follows that he is at work without intermediary in everything that is active, but without excluding the activity of nature or of free will. (Aquinas - Selected Philosophical Writings (Oxford) p.304)
God acts perfectly as a primary cause but needs nature’s activity as a secondary cause. God could, of course, produce the effects of nature without nature, but nevertheless wills them to be done through nature so that order be preserved in things. (Aquinas - Selected Philosophical Writings (Oxford) p.305)

God Substance
Moreover, one shouldn’t attribute to God, who is utterly perfect, what is utterly imperfect. Now existing, like ultimate matter, is utterly imperfect. Now existing, like ultimate matter, is utterly imperfect: ultimate matter is indeterminate relative to every form, and in the same way existing is utterly imperfect and indeterminate relative to every special category [of being]. So, if an ultimate matter doesn’t belong in God, neither should one attribute existing to God’s substance. (Aquinas - Selected Philosophical Writings (Oxford) p.204)
God existing- his substance - is not the existing common to other things, but an existing distinct from all other existing. So by his very own existing God differs from all other beings. (Aquinas - Selected Philosophical Writings (Oxford) p.204)

How he creates 
And this is why he can make something from nothing, an activity of his which is called creation. And so we read in the book Causes that existence is created, but life and the rest formed: for the causing of being, unqualified, is traced back to the first universal cause, whilst the causing of anything over and above being or specifying it is attributed to secondary causes, which act by forming so to speak the presupposed effect of the universal cause. (Aquinas - Selected Philosophical Writings (Oxford) p.254)
And if we understand the word created strictly, as applying only to subsistent things - made and created in a strict sense because only they exist in a strict sense - then the relationship we are talking of is not something created but con-created. For properly speaking it does not exist but rather belongs in existence as all incidental properties do. (Aquinas - Selected Philosophical Writings (Oxford) p.262)

What he creates
So created things have changed, and creation is, therefore, a change, (Aquinas - Selected Philosophical Writings (Oxford) p.257)
For existence, itself is the most shared effect and the primary one deepest within all other effects. That effect only God can produce of his own power; as the book of Causes says, not even [the heavenly] intelligence can give existence unless God’s power is in them. So God causes every activity inasmuch as every agent is the tool of God’s active power. (Aquinas - Selected Philosophical Writings (Oxford) p.303)

The creation of the earth
The subject for debate is Creation- the first effect of God’s power. And in the seventeenth place, we are asked: Has the world always existed? And it seems it had. (Aquinas - Selected Philosophical Writings (Oxford) p.263)

Why God allows Evil
Augustine: Since God is supremely good, he would not allow any evil at all in his works if he wasn’t sufficiently almighty and good to bring good even from evil. It is, therefore, a mark of his unbounded goodness that God allows evils to exist and draws from the good. (Aquinas - Selected Philosophical Writings (Oxford) p.202)

The punishment of evil acts
The evil of a guilty act, on the other hand, runs counter to the highest good, and from that, the highest good cannot turn away. God then can punish but not cause guilty acts. (Aquinas - Selected Philosophical Writings (Oxford) p.292)

A critic of God’s given evil acts 
Moreover, what causes a cause causes its effect. So since God causes our free choice and that causes sin, God causes sin. (Aquinas - Selected Philosophical Writings (Oxford) p.290)

God has no responsibility for the evils act 
Moreover, Fulgentius says that God is not responsible for what he avenges. But God avenges sin. So he is not responsible for it. (Aquinas - Selected Philosophical Writings (Oxford) p.291)

Where is the bliss of God
Thus High of St Victor comments on the words of pseudo-Dionysius Moving and sharp, writers: Love surpasses knowledge and is greater than understanding, for God is loved rather than understood, and love enters where knowledge is left outside. So bliss consists in love rather than in knowledge, in willing rather than in understanding. (Aquinas - Selected Philosophical Writings (Oxford) p.317)

Humans getting the bliss of God
Now if bliss can’t be attained in this life, death becomes a sine qua non of bliss. So man would be nature desire to die, which is disproved by experience and by St Paul’s authority in 2 Corinthians 5: I do not wish to put off this body but to be further clothed. Human bliss then can be attained in this life. (Aquinas - Selected Philosophical Writings (Oxford) p.318)

A critic on Humans getting the bliss of God
Moreover, no one has attained his ultimate end if someone things remain to be desired, for bliss, Aristotle says, must be satisfying in itself. Now, however perfect in knowledge or virtue or anything else a person is in this life, there always remains something to be desired: many things he doesn’t know, for example. Indeed the goodness of perfection itself remains uncertain during this life since even the wisest and most perfect men can lose their minds because of bodily infirmity. So bliss can’t be had in this life. (Aquinas - Selected Philosophical Writings (Oxford) p.319)

Bliss is not even in our hands 
We must distinguish the essence of activity from the ways in which it can be perfected. Its essence is determined by some native ability, but it is perfected by dispositions. When these are acquired dispositions the activity is totally our doing, but when they are instilled the activity’s perfection derives from the external cause of our dispositions. Now our activity is only called bliss when it is perfected with perfection uniting us to our external goal. So our bliss is not our doing, but God’s. (Aquinas - Selected Philosophical Writings (Oxford) p.331)

Knowing God 
So then, we know that immaterial forms exist, but instead of knowing what they are we know them through denial, causality, and uplifting, as pseudo-Dinysius puts in. And this is who Boethius understands scrutinizing the divine form itself: not as knowing what God is, but as denying all images. (Aquinas - Selected Philosophical Writings (Oxford) p.40)

To name god
For, as we have said, all words used of God come from creatures. But to apply names of creatures to God - calling him a rock or a lion, for example - is to use a metaphor. So the words we use of God apply to him metaphorically. (Aquinas - Selected Philosophical Writings (Oxford) p.219)
For the meaning of a word is our mental conception of the thing meant. Now, because the mind knows God from creatures, the conceptions it forms in order to understand God correspond to the conceptions it forms in order to understand God correspond to the perfections that issue from God into creatures. In creatures, these shared perfections are many and various, but in God, they pre-exist in a simple unity. (Aquinas - Selected Philosophical Writings (Oxford) p.222)

To attribute God
This multiplicity of attributes is not at all to be found in God as if he himself, in reality, was multiple; nevertheless, he in his own simple perfection matches the multiplicity of these attributes, so that they can be truly said of him. And this is what Ibn Rushd meant. (Aquinas - Selected Philosophical Writings (Oxford) p.239)


What is divine
So philosophy treats divine things only as of the universal beginnings of things, in that teaching which lays down whatever is common to all beings, having as its subject-matter being as such; and that is the science they call divine science. (Aquinas - Selected Philosophical Writings (Oxford) p.28)
These divine things then, because they are at the beginning of all beings and yet are complete things in their own right, we can study in two ways: as the common beginnings of all being, and as things themselves. (Aquinas - Selected Philosophical Writings (Oxford) p.28)

The divine is unchanging
And such things are divine, since, as Aristotle says, if they're anywhere exists something divine it must surely be in such a nature, namely, immaterial and unchanging. (Aquinas - Selected Philosophical Writings (Oxford) p.28)

Where is the divine
The unseen things of God have been clearly seen by understanding the things he has made. (Aquinas - Selected Philosophical Writings (Oxford) p.28)

Divine is in imagination
Aristotle says the intellect can’t operate without images. In divine matters then we must have recourse to the imagination. (Aquinas - Selected Philosophical Writings (Oxford) p.39)

The divine understanding 
This is the sense in which being and substance and potentiality and actuality exist outside matter and change, not depending on matter and change for their existence as mathematical objects do, which can exist only within matter although they can be understood abstracted from matter-as-perceptible. (Aquinas - Selected Philosophical Writings (Oxford) p.29)

Joy & Sadness
Antithetic states
Good and Bad
Âncora 1
Principles of Nature
Potentiality & Actuality
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