METAPHYSICS
BOOK IITHE SEARCH FOR TRUTH AND CAUSES
CONTENTS
LESSON 1
The Acquisition of Truth: Its Ease and Its Difficulty
ARISTOTLE’S TEXT Chapter 1: 993a 30-993b 19
144. Theoretical, i.e., speculative, knowledge of truth is in one sense difficult and in another, easy.
145. An indication of this is found in the fact that, while no one can attain an adequate knowledge of it, all men together do not fail, because each one is able to say something true about nature.
146. And while each one individually contributes nothing or very little to the truth, still as a result of the combined efforts of all a great amount of truth becomes known.
147. Therefore, if the situation in the case of truth seems to be like the one which we speak of in the proverb “Who will miss a door?” then in this respect it will be easy to know the truth.
148. But the fact that we cannot simultaneously grasp a whole and its parts shows the difficulty involved.”
149. However, since the difficulty is twofold, perhaps its cause is not in things but in us; for just as the eyes of owls are to the light of day, so is our soul’s intellective power to those things which are by nature the most evident of all.
150. Now it is only right that we should be grateful not merely to those with whose views we agree but also to those who until now have spoken in a superficial way; for they too have made some contribution because they have made use of the habit which we now exercise. Thus if there had been no Timotheus, we would not have a great part of our music; and if there had been no Phrynis, there would have been no Timotheus. The same is true of those who have made statements about the truth; for we have accepted certain opinions from some of them, and others have been the cause of them attaining their knowledge as they have been the cause of us attaining ours.
COMMENTARY
273. Having criticized the ancient philosophers’ opinions about the first principles of things, with which first philosophy is chiefly concerned, the Philosopher now begins to establish what is true.
First philosophy considers truth in a different way than the particular sciences do. Each of the particular sciences considers a particular truth out a definite class of beings; e.g., geometry deals with the continuous quantities of bodies, and arithmetic with numbers; whereas first philosophy considers what is universally true of things. Therefore, it pertains to this science to consider in what respects man is capable of knowing the truth.
274. First, he states what he intends to prove. He says that “theoretical knowledge,” i.e., the contemplative or speculative understanding of truth, is in one sense easy and in another, difficult.
275. An indication of this (145).
Second, he explains what he intends to prove: first, in what sense it is easy to know the truth; and second (278), in what sense it is difficult (“But the fact”). He shows in what sense it is easy to know the truth, by giving three indications:
The first is this: while no man can attain a complete knowledge of the truth, still no man is so completely devoid of truth that he knows nothing about it. This is shown by the fact that anyone can make a statement about the truth and the nature of things, which is a sign of intellectual reflection.
276. And while each one individually (146).
Here he gives the second indication. He says that, while the amount of truth that one man can discover or contribute to the knowledge of truth by his own study and talents is small compared with a complete knowledge of truth, nevertheless what is known as a result of “the combined efforts” of all, i.e., what is discovered and collected into one whole, becomes quite extensive. This can be seen in the case of the particular arts, which have developed in a marvelous manner as a result of the studies and talents of different men.
277. Therefore, if the situation (147).
Third, he shows that the same thing is true by citing a common proverb. He concludes from the foregoing that since anyone can attain some knowledge of the truth, even though it be little, the situation in the case of knowledge is like the one that we speak of in the proverb “Who will miss a door?” i.e., the outer door of a house. For it is difficult to know what the interior of a house is like, and a man is easily deceived in such matters; but just as no one is mistaken about the entrance of a house, which is evident to all and is the first thing that we perceive, so too this is the case with regard to the knowledge of truth; for those truths through which we enter into a knowledge of others are known to all, and no man is mistaken about them. Those first principles which are naturally apprehended are truths of this sort, e.g., “It is impossible both to affirm and deny something at the same time,” and “Every whole is greater than each of its parts,” and so on. On the other hand, there are many ways in which error may arise with respect to the conclusions into which we enter through such principles as through an outer door. Therefore, it is easy to know the truth if we consider that small amount of it which is comprised of self-evident principles, through which we enter into other truths, because this much is evident to all.
278. But the fact that we cannot (148).
Here he explains in what sense it is difficult to know the truth. He says that our inability to grasp the whole truth and a part of it shows the difficulty involved in the search for truth. In support of this we must consider his statement that the truth through which we gain admission to other truths is known to all. Now there are two ways in which we attain knowledge of the truth.
The first is the method of analysis, by which we go from what is complex to what is simple or from a whole to a part, as it is said in Book I of the Physics that the first objects of our knowledge are confused wholes. Now our knowledge of the truth is perfected by this method when we attain a distinct knowledge of the particular parts of a whole.
The other method is that of synthesis, by which we go from what is simple to what is complex; and we attain knowledge of truth by this method when we succeed in knowing a whole. Thus the fact that man is unable to know perfectly in things a whole and a part shows the difficulty involved in knowing the truth by both of these methods.
279. However, since the difficulty is twofold (149).
He gives the reason for this difficulty. Here too it must be noted that, in all cases in which there is a certain relationship between two things, an effect can fail to occur in two ways, i.e., because of either one of the things involved. For example, if wood does not burn, this may happen either because the fire is not strong enough or because the wood is not combustible enough. And in a similar way the eye may be prevented from seeing a visible object either because the eye is weak or because the visible object is in the dark. Therefore, in like manner, it may be difficult to know the truth about things either (1) because things themselves are imperfect in some way or (2) because of some weakness on the part of our intellect.
280. (1) Now it is evident that we experience difficulty in knowing the truth about some things because of the things themselves; for since each thing is knowable insofar as it is an actual being, as will be stated below in Book IX (1894) of this work, then those things which are deficient and imperfect in being are less knowable by their very nature; e.g., matter, motion, and time are less knowable because of the imperfect being which they have, as Boethius says in his book The Two Natures.
281. Now there were some philosophers who claimed that the difficulty experienced in knowing the truth is wholly attributable to things themselves, because they maintained that nothing is fixed and stable in nature but that everything is in a state of continual change, as will be stated in Book IV (683) of this work. But the Philosopher denies this, saying that even though the difficulty experienced in knowing the truth can perhaps be twofold because of different things, i.e., our intellect and things themselves, still the principal source of the difficulty is not things but our intellect.
282. He proves this in the following way. If this difficulty were attributable principally to things, it would follow it we would know best those things which are most knowable by nature. But those things which are most knowable by nature are those which are most actual, i.e., immaterial and unchangeable things, yet we know these least of all.
Obviously, then, the difficulty experienced in knowing the truth is due principally to some weakness on the part of our intellect. From this it follows that our soul’s intellectual power is related to those immaterial beings, which are by nature the most knowable of all, as the eyes of owls are to the light of day, which they cannot see because their power of vision is weak, although they do see dimly lighted things.
283. But it is evident that this simile is not adequate; for since a sense is a power of a bodily organ, it is made inoperative as a result of its sensible object being too intense. But the intellect is not a power of a bodily organ and is not made inoperative as a result of its intelligible object being too intelligible. Therefore, after understanding objects that are highly intelligible our ability to understand less intelligible objects is not decreased but increased, as is stated in Book III of The Soul.
284. Therefore it must be said that a sense is prevented from perceiving some sensible object for two reasons: first, (1) because a sensory organ is rendered inoperative as a result of its sensible object being too intense (this does not occur in the case of the intellect); second, (2) because of some deficiency in the ability of a sensory power to perceive its object; for the powers of the soul in all animals do not have the same efficacy. Thus, just as it is proper to man by nature to have the weakest sense of smell, in a similar way it is proper to an owl to have the weakest power of vision, because it is incapable of perceiving the light of day.
285. Therefore, since the human soul occupies the lowest place in the order of intellective substances, it has the least intellective power. As a matter of fact, just as it is by nature the actuality of a body, although its intellective power is not the act of a bodily organ, in a similar way it has a natural capacity to know the truth about corporeal and sensible things. These are less knowable by nature because of their materiality, although they can be known by abstracting sensible forms from phantasms. And since this process of knowing truth befits the nature of the human soul insofar as it is the form of this kind of body (and whatever is natural always remains so), it is possible for the human soul, which is united to this kind of body, to know the truth about things only insofar as it can be elevated to the level of the things which it understands by abstracting from phantasms. However, by this process it cannot be elevated to the level of knowing the quiddities of immaterial substances because these are not on the same level as sensible substances. Therefore it is impossible for the human soul, which is united to this kind of body, to apprehend separate substances by knowing their quiddities.
286. For this reason the statement which Averroes makes at this point in his Commentary is evidently false, i.e., that the Philosopher does not prove here that it is just as impossible for us to understand abstract substances as it is for a bat to see the sun. The argument that he gives is wholly ridiculous; for he adds that, if this were the case, nature would have acted in vain because it would have made something that is naturally knowable in itself to be incapable of being known by anything else. It would be the same as if it had made the sun incapable of being seen.
This argument is not satisfactory for two reasons. First, the end of separate substances does not consist in being understood by our intellect, but rather the converse. Therefore, if separate substances are not known by us, it does not follow that they exist in vain; for only that exists in vain which fails to attain the end for which it exists. Second, even though the quiddities of separate substances are not understood by us, they are understood by other intellects. The same is true of the sun; for even though it is not seen by the eye of the owl, it is seen by the eye of the eagle.
287. Now it is only right (150).
He shows how men assist each other to know the truth; for one man assists another to consider the truth in two ways—directly and indirectly.
One is assisted directly by those who have discovered the truth; because, as has been pointed out, when each of our predecessors has discovered something about the truth, which is gathered together into one whole, he also introduces his followers to a more extensive knowledge of truth.
One is assisted indirectly insofar as those who have preceded us and who were wrong about the truth have bequeathed to their successors the occasion for exercising their mental powers, so that by diligent discussion the truth might be seen more clearly.
288. Now it is only fitting that we should be grateful to those who have helped us attain so great a good as knowledge of the truth. Therefore he says that “It is only right that we should be grateful,” not merely to those whom we think have found the truth and with whose views we agree by following them, but also to those who, in the search for truth, have made only superficial statements, even though we do not follow their views; for these men too have given us something because they have shown us instances of actual attempts to discover the truth. By way of an example he mentions the founders of music; for if there “had been no Timotheus,” who discovered a great part of the art of music, we would not have many of the facts that we know about melodies. But if Timotheus had not been preceded by a wise man named “Phrynis,” he would not have been as well off in the subject of music. The same thing must be said of those philosophers who made statements of universal scope about the truth of things; for we accept from certain of our predecessors whatever views about the truth of things we think are true and disregard the rest. Again, those from whom we accept certain views had predecessors from whom they in turn accepted certain views and who were the source of their information.
The Supreme Science of Truth, and Knowledge of Ultimate Causes
ARISTOTLE’S TEXT Chapters 1 & 2: 993b 19-994b 11
Finally, he mentions the formal cause. He says that it is also impossible to proceed to infinity in the case of the “quiddity,” i.e., the formal cause, which the definition signifies. However, he omits examples because these are evident, and because it was shown in Book I of the Posterior Analytics that it is impossible to proceed to infinity in the matter of predication, as though animal were predicated quidditatively of man, living of animal, and so on to infinity.
The Existence of a First Efficient Cause and of a First Material Cause
ARISTOTLE’S TEXT Chapter 2: 994a 11-994b 9
305. Neither is it possible (154)
308. Now there are two ways in which (155)
310. We say, then, that a man (156).
311. This is why changes (157)
312. Now in neither way (158).
314. At the same time it is impossible (159).
315. But since someone could say that the philosophers did not hold that the first material principle is eternal because it remains numerically one eternally but because it is eternal by succession (as if the human race were held to be eternal), he therefore excludes this from the first supposition. He says that since generation is not infinite in an upward direction but stops at a first material principle, then if there is a first material principle by reason of whose corruption other things come into being, it must not be the eternal principle of which the philosophers speak. The reason is that the first material principle cannot be eternal if other things are generated by reason of its corruption, and it in turn is generated by the corruption of something else. It is evident, then, that a thing comes from this first material principle as something imperfect and potential which is midway between pure nonbeing and actual being, but not as water comes from air by reason of the latter’s corruption.
The Existence of a First in Final and Formal Causes
ARISTOTLE’S TEXT Chapter 2: 994b 9-994b 31
161. Now those who posit infinity do away with the nature of the good without realizing it.
162. But no one will attempt to do anything unless he thinks he can carry it through to its term.
164. Nor can the quiddity be reduced to a definition which adds to the defining notes.
317. Now those who posit infinity (161).
318. But no one will attempt (162).
320. Nor can the quiddity (164).
322. For a prior definition (165).
323. Again, those who speak (166).
327. This case is not like (168).
328. But it is necessary (169).
330. Again, if the classes (170).
He shows that the classes of causes are not infinite in number, and he uses the following argument. We think that we have scientific knowledge of each thing when we know all its causes. But if there were an infinite number of causes in the sense that one class of cause may be added to another continuously, it would be impossible to traverse this infinity in such a way that all causes could be known. Hence in this way too the knowing of things would be destroyed.
The Method to Be Followed in the Search for Truth
ARISTOTLE’S TEXT Chapter 3: 994b 32-995a 20
335. For this reason one must be trained (174).