LESSON 14

Seven Arguments against the View that Truth Consists in Appearances

Chapter 5: 1010b 1-1011a 2

             369. Now concerning the truth that not everything which appears is true, the following points must be taken into consideration: first, that a sense is not false with regard to its proper object, but imagination is not the same as a sense.

             370. Second, that it is surprising if some should raise the question whether continuous quantities are as great and colors really such as they appear to those who are at a distance or as they appear to those who are close at hand, and whether things are such as they appear to those who are healthy or to those who are ailing, and whether heavy things are such as they appear to those who are weak or to those who are strong, and whether those things are true which appear to those who are asleep or to those who are awake. For it is clear that they do not think so. Therefore no one who is in Lybia, having dreamed that he was in Athens, would go to the Odeon.

             371. Again, concerning future things, as Plato says, the opinion of a physician and that of a person who is ignorant of the art of medicine are not of equal value as to whether someone will get well or not.

             372. Again, in the case of the senses the perception of a foreign object and that of a proper object, or that of a kindred object and that of the object of the sense concerned, are not of equal value. In the case of colors it is sight and not taste which passes judgment; and in the case of flavors it is taste and not sight which does this.

             373. And no one of these senses ever affirms at the same time about the same subject that it is simultaneously both so and not so. Nor at another time does it experience any difficulty about a modification, but only about the object of which the modification is an accident. I mean, for example, that the same wine, either as a result of a change in itself or in the body, might seem at one time sweet and at another not. But sweetness, such as it is when it exists, has never changed; but one is always right about it, and sweetness itself is necessarily such as it is.

             374. Yet all these theories destroy this, for just as things will have no substance, neither will they have any necessity; for that is necessary which cannot be in one way and in another. Hence, if anything is necessary, it will not be both so and not so.

             375. And in general if only the sensible actually exists, there would be nothing if living things did not exist; for there would be no senses. Therefore the position that neither sensible objects nor sensory perceptions would exist is perhaps true, for these are modifications of the one sensing. But that the underlying subjects which cause perception should not exist apart from perception is impossible; for a perception is not the perception of itself, but there is some other thing besides the perception which must be prior to the perception. For that which causes motion is naturally prior to that which is moved, and this is no less true if they are correlative terms.

COMMENTARY

             692. Here he begins to argue dialectically against the opinion that truth if equivalent to appearances; and in regard to this he does two things. First (369:C 718), he rejects this opinion. Second (381:C 718), he draws his intended conclusion ("Let this suffice").

             In regard to the first he does two things. First, he argues dialectically against those who held this opinion because of some theory or difficulty. Second (376:C 708), he argues against those who held this opinion because of insolence ("Now there are some").

             In regard to the first part (369) he gives seven arguments. The first of these is as follows: it has been shown (367:C 690) that not all things are changeable, and "concerning the truth that not everything which appears is true," these points must be considered. First, the proper cause of falsity is not the senses but the imagination, which is not the same as the senses. That is to say, the diversity of judgments made about sensible objects is not attributable to the senses but to the imagination, in which errors are made about sensory perceptions because of some natural obstacle. Now imagination is not the same as perception, as is proved in Book III of The Soul, but is a motion produced as a result of actual sensing. Therefore in attributing to the senses this diversity of judgments by which one person is considered to have a false perception of a particular object about which another has a true perception, they do not proceed as they should.

Another translation states this better, saying, "And, first, it must be understood that a sense is not false with regard to its proper object," implying that no sense makes a mistake about its own proper object; for example, sight is not mistaken about colors. From this it is evident that the judgment which a sense makes about its proper sensible object is a definite one, so that there must be some definite truth in the world.

             693. And if someone raises the objection that error sometimes arises even with regard to proper sensibles, his answer is that this is attributable not to the senses but to the imagination; for when the imagination is subject to some sort of abnormality, it sometimes happens that the object apprehended by a sense enters the imagination in a different way than it was apprehended by the sense. This is evident, for example, in the case of madmen, in whom the organ of imagination has been injured.

             694. Second, that it is (370).

             Then he gives his second argument, and it runs thus: it is surprising if some "should raise the question," or "be puzzled," as another text says, whether continuous quantities are such as they appear to those who are at a distance or to those who are close at hand. For it is just about self-evidently true that a sense judges quantities which are close at hand to be such as they are, and those which are far away to be smaller than they are, because what seems farther away appears small, as is proved in the science of optics.

             695. The same thing applies if someone raises the question whether colors are such as they appear to those who are close at hand; for it is evident that the farther an agent's power is extended when it acts, the more imperfect is its effect; for fire heats those things which are far away to a lesser degree than those which are close at hand. And for the same reason the color of a perfect sensible body does not change that part of the transparent medium which is far away from it as completely as it changes that part which is close to it. Hence the judgment of a sense is truer about sensible colors in things close at hand than it is about those in things far away.

             696. The same thing is also true if someone asks whether things are such as they appear to those who are healthy or "to those who are ailing," i.e., those who are ill. For healthy people have sensory organs which are well disposed, and therefore the forms of sensible things are received in them just as they are; and for this reason the judgment which healthy people make about sensible objects is a true one. But the organs of sick people are not properly disposed, and therefore they are not changed as they should be by sensible objects. Hence their judgment about such objects is not a true one. This is clear with regard to the sense of taste; for when the organ of taste in sick people has been rendered inoperative as a result of the humors being destroyed, things which have a good taste seem tasteless to them.

             697. The same thing also applies regarding the question whether things having weight are as heavy as they seem to those who are weak or to those who are strong; for it is clear that the strong judge about heavy things as they really are. But this is not the case with the weak, who find it difficult to lift a weight not only because of the heaviness of it (and this sometimes happens even with the strong) but also because of the weakness of their power, so that even less heavy things appear heavy to them.

             698. The same thing again applies if the question is raised whether the truth is such as it appears to those who are asleep or to those who are awake. For the senses of those who are asleep are fettered, and thus their judgment about sensible things cannot be free like the judgment of those who are awake and whose senses are unfettered. For it has been pointed out above that it would be surprising if they should be perplexed, because it appears from their actions that they are not perplexed, and that they do not think that all of the above-mentioned judgments are equally true. For if someone in Lybia seems in his dreams to be in Athens, or if someone in Paris seems in his dreams to be in Hungary, he does not when he awakens act in the same way that he would if he were to perceive this when he is awake. For if he were awake in Athens, he would go to the Odeon, i.e., a building in Athens; but he would not do this if he had merely dreamed it. It is clear, then, that he does not think that what appears to him when he is asleep and what appears when he is awake are equally true.

             699. We can argue in the same way with regard to the other issues mentioned above; for even though men often raise questions about these issues, they are not in their own mind perplexed about them. Hence it is clear that their reason for holding to be true everything which appears, is invalid; for they held this position because of the impossibility of deciding which of several opinions is the truer, as has been stated above (353:C 663).

             700. Again, concerning future (371).

             Here he gives his third argument. He says that in the case of future events, as Plato points out, the opinion of a physician and that of a person who is ignorant of the art of medicine are not "of equal value," i.e., equally important, certain, true or acceptable, as to the future possibility of some sick person being cured or not. For, while a physician knows the cause of health, this is unknown to someone who is ignorant of the art of medicine. It is clear, then, that the opinion which some held that all opinions are equally true is a foolish one.

             701. Again, in the case (372).

             He gives his fourth argument, which runs thus: in the case of sensible objects the judgment which a sense makes about some sensible object foreign to it and that which it makes about its proper sensible object are not of equal "value," i.e., equally true and acceptable; for example, sight and taste do not make the same sort of judgment about colors and flavors, but in the case of colors the judgment of sight must be accepted, "and in the case of flavors," or savors, the judgment of taste must be accepted. Hence, if sight judges a thing to be sweet and taste judges it to be bitter, taste must be accepted rather than sight.

             702. And in the same way too the judgment which a sense makes about its proper sensible object and the one which it makes about something akin to its proper object are not of equal value. Now those things which are said here to be akin to proper sensible objects are called common sensibles, for example, size, number and the like, about which a sense is deceived to a greater degree than it is about its proper sensible object, although it is deceived about them to a lesser degree than it is about the sensible objects of another sense or about things which are called accidental sensible objects. Hence it is clearly foolish to say that all judgments are equally true.

             703. And no one (373).

             He now gives his fifth argument. He says that no sense affirms at one instant of time that a thing is simultaneously both so and not so. For sight does not at the same moment affirm that something is white and not white or that it is two cubits and not two cubits or that it is sweet and not sweet. But while a sense's power of judging may seem at different times to form opposite judgments about the same thing, still from this judgment no difficulty ever arises about the sensible modification itself, but only about the subject of this modification. For example, if we take the same subject, wine, sometimes it appears to the sense to taste sweet and sometimes not. This happens either because of some change in the sentient body, i.e., in the organ, which is infected by bitter humors, so that whatever it tastes does not seem sweet to it, or else because of some change in the wine itself. But the sense of taste never changes its judgment without judging sweetness itself to be such as it considered it to be in the sweet thing when it judged it to be sweet; but about sweetness itself it always makes a true affirmation, and always does this in the same way. Hence, if the judgment of a sense is true, as these men claimed, it also follows that the nature of sweetness is necessarily such as it is; and thus something will be definitely true in reality. And it also follows that both an affirmation and a negation can never be true at the same time, because a sense never affirms that something is both sweet and not sweet at the same time, as has been stated.

             704. Yet all these (374).

             He gives the sixth argument. He says that, just as all of the above-mentioned theories or opinions destroy substantial predicates, as has been shown above (341:C 625), in a similar way they destroy all necessary predicates. For it follows that nothing could ever be predicated of anything else either substantially or necessarily. That nothing could be predicated of anything else substantially is clear from what has been stated above. That nothing could be predicated of anything else necessarily is proved as follows. That is necessary which cannot be otherwise than it is; therefore, if everything which is can exist in one way or in another way, as is held by those who say that contradictories and opposite opinions are true at the same time, it follows that nothing is necessary in the world.

             705. And in general (375).

             Then he gives the seventh argument. He says that, if everything which appears is true, and a thing is true only insofar as it appears to the senses, it follows that a thing exists only insofar as it is actually being sensed. But if something exists only in this way, i.e., insofar as it is being sensed, then it follows that nothing would exist if the senses did not exist; and this would follow if there were no animals or living things. But this is impossible.

             706. For this can be true, that sensibles under the aspect of their sensibility do not exist; i.e., if they are considered under the aspect of sensibles actualized, they do not exist apart from the senses, for they are sensibles actualized insofar as they are present in a sense. And according to this every actualized sensible is a certain modification of the subject sensing, although this would be impossible if there were no sensory beings. But that the sensible objects which cause this modification in a sense should not exist is impossible. This becomes clear as follows: when some subsequent thing is removed it does not follow that a prior thing is removed. But the thing producing the modification in a sense is not the perception itself, because a perception is not the perception of itself but of something else, and this must be naturally prior to the perception just as a mover is prior to the thing which is moved. For sight does not see itself but sees color.

             707. And even if someone were to raise the objection that a sensible object and a sense are correlative and thus naturally simultaneous, so that when one is destroyed the other is destroyed, Aristotle's thesis is still true; for what is potentially sensible is not said to be relative to a sense because it is referred to a sense, but because the sense is referred to it, as is stated in Book V of this work (496:C 1027). It is clearly impossible, then, to say that some things are true because they appear to the senses; yet this is what those men maintain who claim that all appearances are true, as is evident from the foregoing statements.