Lecture 1 — The dignity, utility, order, and difficulty of this science

Holding as we do that knowledge is of good and honorable things, yet that some kinds of knowledge are more so than others, either because they are more certain or because they are about better and more wonderful things, with good reason we give a primary place, for both these reasons, to an inquiry about the soul.

Indeed, knowledge of the soul would seem to help greatly in acquiring all truth, especially about the natural world; for it is, as it were, the principle of living things.

We seek, then, to consider and know, first, its nature and substance, then whatever qualities belong to it. Of these latter, some seem to be proper passions of the soul alone, others to be shared in common and to exist in living beings on account of it.

To ascertain, however, anything reliable about it is one of the most difficult of undertakings. For, such a question being common to many other things—I mean, an inquiry into the substance, and what each thing is—it might seem to some that one definite procedure were available for all things of which we wished to know the substance, as there is demonstration for the accidental properties of things. So we should have to discover what is this one method.

But if there is no one method for determining what a thing is, our inquiry becomes decidedly more difficult, for we shall have to find what procedure belongs to each case; for then it would be clear whether it is a certain demonstration, or a division, or even some other procedure. And there are still many puzzles and uncertainties for which answers must be found. For there are different principles for different things, for instance, in the case of numbers and surfaces.

Perhaps the first thing needed is to divide off the genus of the subject and to say what it is—I mean, whether it be a particular thing and substance, or a quality, or a quantity, or any other of the different categories.

Further, whether it is among things in potency or is an actuality—no small distinction. Again, whether it is divisible or indivisible, and whether every soul is like in species or not, and if not, whether they differ specifically or generically.

For those who at present talk of and discuss the soul seem to deal only with the human soul. One must be careful not to leave unexplored the question whether there is a single account of it, as there is of “animal,” or a different one for each one—for example, for horse, dog, man, or god. Now, “animal” as a universal is nothing, or is something secondary. And we must say the same of any other common predicate.

Further, if there are not many souls, but only many parts, we must ask whether one ought to look first at the whole soul or its parts. It is difficult to determine what sorts are by nature diverse from one another, and whether one ought to look first at the parts or their activities—for instance, at understanding or at the intellectual power, at sensing or at the sensitive power; and likewise in other instances.

But if one is to examine first the activities, it might be asked whether one should not first inquire about their objects, for instance, the sensible thing before the sensitive power, and the intelligible thing before the intellectual power.

Now, it seems that not only does knowing the substance help one to know the causes of the accidents of substances, as in mathematics, knowing what the straight is and what the curved is, and what a line is and what a plane is helps one know how many right angles equal the angles of a triangle. But, conversely, accidental qualities contribute much to knowing what a thing is. For when we can give an account of such accidents (either some or all) according to appearances, then we shall best have something to say about the substance. For the principle of every demonstration is what a thing is. Hence, whatsoever definitions do not afford us a knowledge of accidents, or even a fair conjecture about them, are obviously all said dialectically and are empty.

1. Holding as we do that knowledge (402a1). In studying any genus of things, it is first of all necessary, as the Philosopher says in Parts of Animals, to consider separately what is common, and afterwards what is proper to each member of the genus. (Aristotle (384–322 BC), Parts of Animals* 1.1, 639a15–29; 1.5, 645a36–b13.)* Such is Aristotle’s method in first philosophy; for at the beginning of the Metaphysics, he investigates and contemplates things common to being as being, and only then does he go on to things proper to each being. The reason for this procedure is that it saves frequent repetition. Now, there is a certain genus of all things that are ensouled; hence, in contemplating them, the first thing one must do is consider what ensouled things have in common, and afterwards what each has peculiar to itself. What they have in common is a soul; in this they are all alike. Therefore, in conveying knowledge about ensouled things, one must first convey it about the soul as that which is common to them all. Thus, when Aristotle sets out to treat of ensouled things, he begins with the soul; after which, in subsequent books, he determines the properties of particular ensouled beings.

2. In the treatise that we are holding in our hands about the soul, we find, first, an introduction: in this, the author does the three things that should be done in any introduction. (Cf. Marcus Tullius Cicero (106–43 BC), De inventione, bk. 1, ch. 15.) For in writing an introduction one has three objects in view: first, to gain the reader’s good will; second, to dispose him to learn; third, to win his attention.

The first object one achieves by showing the reader the value of the knowledge in question; the second, by explaining the plan and divisions of the treatise; the third, by warning him of its difficulties. And all this Aristotle does here.

First, he points out the high value of the science he is introducing.

Second, at we seek, then (402a7; [8]), he explains the plan of the treatise.

Third, at to ascertain, however, anything reliable (402a10; [9]), he warns of its difficulty.

Under the first point, he explains:

first, the dignity of this science;

and then, at indeed, knowledge (402a4; [7]), its utility.

3. As regards, then, the said dignity, we should note that, while all knowledge is good and even honorable, one science can surpass another in this respect. All knowledge is obviously good because the good of anything is that according to which the thing has perfect being, which all things seek after and desire; therefore, since knowledge is man’s perfection as a man, knowledge is man’s good.

Now, of good things some are praiseworthy, namely, those which are ordered to some end—as we praise a good horse because it runs well; while other good things are also honorable, namely, those that exist for their own sake; for we give honor to ends, not means. But of the sciences, some are practical, others speculative, the difference being that the former are for the sake of some work to be done, while the latter are for their own sake. The speculative sciences are, therefore, honorable as well as good, but the practical are only praiseworthy. Every speculative science, then, is both good and honorable.

4. Yet even among the speculative sciences there are degrees of goodness and honorableness. For every science is praised due to its act, and every act is praised based on two things: its object and its manner or quality. Thus, building is a better activity than bed-making because its object is better, whereas when one makes the same thing and in the same respect, the quality itself established the degree, since inasmuch as the manner of the building is better, the building is also better. Considering science, then, or its act from the point of view of the object, that science is nobler which is concerned with better and nobler things; but from the point of view of its quality or manner, the nobler science is that which is more certain. One science, then, is reckoned nobler than another either because it concerns better and nobler objects or because it is more certain.

5. But there is this difference between sciences: some excel in certainty and yet are concerned with less honorable things, while others are concerned with more honorable and better things and are nevertheless less certain. All the same, that science is the better which is about better and more honorable things. For, as the Philosopher observes in Parts of Animals, we have a greater desire for even a little knowledge of more honorable and exalted things—even for a conjectural, that is, probable sort of knowledge—than for a great and certain knowledge of less noble things. (Aristotle, Parts of Animals 1.5, 644b24–25, 31–35.) For the former is noble in itself and from its substance, but the latter has it only through its quality or mode.

6. Now, this science of the soul has both merits. It has certainty; for everyone experiences within himself both that he has a soul and that the soul gives him life. Also, this science is about nobler things; for among lower creatures, the soul is quite noble.

This is what Aristotle means here when he says, holding as we do that knowledge (402a1), that is, science, is of good, that is, is in the number of good things, and honorable things.

And one science is better and nobler than another because it is about better things, that is, things that are good in their nature, and more wonderful things, that is, things whose cause is unknown. For both these reasons, he goes on to say, we give a primary place to an inquiry about the soul.

He uses the term inquiry because he is going to discuss the soul in a summary way, without attempting, in this treatise, a thorough examination of all things that pertain to the soul itself. As to the words, a primary place, if they are taken as applying to the whole of natural science, then they refer to superiority in dignity and not to priority in order; but if they refer to the science of ensouled things only, they mean priority of order.

7. Then, at indeed, knowledge (402a4), he gains the reader’s good will by showing the utility of this science. Knowledge of the soul, he says, would seem to help greatly in acquiring all truth treated in the other sciences. For it can be of considerable service to all parts of philosophy. (Themistius (317 – ca. 388 AD), In De anima, trans. Guilelmo, ed. Verbeke, ms. Toledo Cabildo, 47.12, f. 1ra.)

In first philosophy, it is impossible to come to knowledge of the divine and highest causes except through things that we acquire first from the power of understanding.

In fact, as regards moral philosophy, we cannot attain perfectly the science of morals unless we know the powers of the soul; this is why, in the Ethics, the Philosopher assigns certain virtues to the different powers of the soul. (Aristotle, Nicomachean Ethics 1.13, 1103a3–4; 3.10, 1117b23–24; 6.1, 1138b35–1139a1, 1139a15–16; 6.11, 1143b16; 6.12, 1144a2; cf. Aquinas, Commentary on Ethics, bk. 1, lect. 20.)

So, too, it is useful for the natural scientist, because many of the natural things he studies possess soul, and the soul itself is the source and principle of every motion (Themistius, In De anima, f. 1rb1–2.) in all ensouled things. For the soul is, as it were, the principle of living things. The phrase, as it were, does not express a likeness; it is descriptive.

8. Next, at we seek, then (402a7), he states the plan of his treatise, saying that we are to contemplate and know what the soul is, that is, its nature and substance; and then whatever qualities belong to it, that is, its passions.

But in the latter, a diversity appears: for while some of the soul’s passions, such as understanding and speculative knowledge, seem to belong to the soul alone, others, such as pleasure and pain, sensation, and imagination, (Themistius, In De anima, f. 1rb.) though a result of the soul itself, seem to be shared in common by all animals.

9. Then, at to ascertain (402a10), he introduces the difficulty of this study; and this, from two points of view.

It is hard, first, to know the substance of the soul;

and second, it is hard to know its accidents or proper passions (40313; [16]).

As to the substance, there is a double difficulty:

first, as to how the soul itself ought to be defined;

and then, as to the elements of the definition (402a22; [10]).

He remarks, therefore, that while knowledge of the soul would be valuable, it is not easy to know just what the soul is. Now, this is a difficulty in studying anything; the inquiry into the substance, and what each thing is, is common to the study of soul and of many other things. The first difficulty is that we do not know what path to follow to the definition; for some say we should use demonstration, others, the method of division, still others, one of composition. Aristotle himself preferred the method of composition.

10. The second difficulty concerns the elements of the definition. A definition manifests a thing’s essence; and this cannot be grasped apart from knowing its principles. But different things have different principles, so it is hard to know from which things the principles are drawn.

Hence, the things that engender difficulty for those formulating a definition reduce to three:

first, concerning the soul’s substance;

second, concerning its parts;

third, concerning that necessary contribution to a definition that comes from knowing the soul’s accidents.

11. As regards the substance of soul, there is a doubt about the genus, for in the definition of each and every thing, we seek this first—that is, that we know its genus—so one must ask: in what genus should the soul be placed? In the genus of substance, or in quantity, or in quality? And not only must we decide upon the ultimate genus, but also on the proximate one; thus, we do not define man as a substance, but as an animal. (Themistius, In De anima, f. 1va4–5.)

And if soul is found to be in the genus of substance, we shall still have to seek whether it is actual or potential substance, since every genus is spoken of in these two ways, either as potential or as actual.

Also, since substances are either composite or simple, we shall have to ask whether the soul is composite or simple, and whether it is divisible or indivisible.

There is also the question whether all souls (Themistius, In De anima, f. 1va34–35.) are of the same species or not; and if they are not of one species, whether they differ specifically or generically.

Again, there is uncertainty as to what is to be included in the definition, for some things are defined as a genus, some as a species; hence, the question whether we should define soul is that of a genus or that of a most specific species.

12. For some inquirers seem to deal only with the human soul. And among the earlier philosophers there were two opinions about the soul.

The Platonists, holding that universals existed separately as the forms or ideas that caused knowledge and being in individual things, maintained that there was a separated soul-in-itself that was the cause and idea of particular souls and from which all that we find in these drew their origin.

On the other hand, there were natural philosophers who maintained that no universal substances exist in the nature of things, and that the only natural things are individuals.

And this raises the question whether, like the Platonists, one ought to look for a single common account of soul, or rather ought one, like the natural philosophers, look for the account of this or that soul, such as the soul of horse, or that of man, or that of god. He says, of god, because they used to believe that the heavenly bodies were gods, and said they were ensouled.

13. However, Aristotle chose to seek an account for each—both a common one of soul and one of each species. But when he says, on this point, that animal as a universal is nothing, or is secondary, we must understand that one can speak of the universal “animal” in two ways: either as universal, that is, as one thing existing in, or predicated of, many individuals; or as animal. And if it be considered as universal, this too is either insofar as it exists in the nature of things or insofar as it exists in the intellect. Insofar as it exists in the nature of things, Plato held that the universal animal did so exist and existed prior to the particular, because, as has been said, he thought that there were separated universals and ideas. Aristotle, however, says that the universal is nothing in the nature of things, and if it is anything at all, it exists after. But if we regard the nature of animal not insofar as it is subject to the intention of universality, then it is something, and something prior, just as what is in potency is prior to what is in act.

14. Then, at further, if there are not many (402b9), Aristotle touches on the difficulties that arise concerning the soul’s powers. For in the soul there are potential parts: the intellectual, the sensitive, and the vegetative. So the question is whether these are different souls, as the Platonists thought, or are they potential parts of the soul.

And if they are potential parts, we must further ask whether we should inquire first into the powers themselves, and then into their acts—for instance, understanding or the intellectual power, and sensing, which is the act, or the sensitive power, which is a potency. And likewise in other acts and powers. And if we should take the acts before the powers, there is still the question whether the objects of these acts should be studied before the powers, for example, the sensible before the sense power or the intelligible before the intellectual power.

15. Next, at now, it seems (402b16), he states the difficulties that arise with regard to things that contribute to a definition of the soul. For these are relevant here because in a definition one must know not only its essential principles but even its accidental ones. For if it were correctly defined and its essential principles could be known, the definition would not need the accidents; but since the essential principles of things are unknown to us, we must make use of accidental differences as indication of the essentials. For example, to be two-footed is not essential, yet it is put in it to indicate the essential. And through such (that is, through accidental differences) we reach the knowledge of the essential ones.

Hence, the difficulty of our present position. It would indeed be easier to know the soul’s accidents if we first knew the what-it-is of the soul, just as in mathematics it is very helpful to know first the “what it was to be” of the straight, and of the curved, and of a plane in order to know how many right angles equal the angels of a triangle. Conversely, a prior examination of accidental qualities contributes much to knowing what a thing is, as has been said. If, therefore, one were to propose a definition from which no knowledge of the accidents of the defined thing could be discovered, such a definition is not the real one, but a remote and dialectical one. But the definition from which a knowledge of the accidents flows is real and based on what is proper and essential to the thing.