LECTIO FIVE

             § 637. After saying that imagination is not the same as opinion he begins to examine it in itself, first stating the question to be treated before proceeding with it at 'If then'. We have seen, he says, that understanding differs from sensation, and that opinion is akin to the former, but imagining to the latter; and now, having finished with the senses, it will be convenient to discuss imagination before tackling the quite distinct problems touching the intellect and opinion.

             § 638. Then, at 'If then', he begins to treat of imagination, and this in two main sections, first proving that the imagination is not to be numbered among those cognitive powers or dispositions by which we discriminate truth from falsehood, or judge things to be true or false; and then, at 'But since it can happen', explaining what in fact the imagination is. The former section subdivides into three. To begin with, he enumerates our various powers or modes of discernment; secondly, he shows that imagination is not one of these, and thirdly, that it is not even a combination of any of them--this part beginning at 'It is therefore evident'.

             First, then, he observes that if it is through imagination that we become conscious of phantasms or appearances (unless the term 'phantasms' is taken metaphorically) imagination would seem to be one of those cognitive dispositions or powers by which things are perceived together with their differences, or are judged according to this or that aspect, truly or falsely, i.e. with a correct or erroneous judgement. (Not that the appearance itself is the same as this discerning or judging.) Now there seem to be four powers or dispositions from which such discernment or judgement proceeds: sense, understanding, opinion and scientific knowledge. Imagination, then, is apparently one of these four.

             § 639. Aristotle mentions these four as being already familiar. Other factors (as they seem to be) in cognition were still, at the time he was writing, not defined with certainty. But having already distinguished sensation from the intellect, he can enumerate here three factors distinct from sense: understanding, opinion and scientific knowledge. Nor is he, apparently, speaking of the understanding as a faculty (i.e. of the intellect); else it would not be set apart from science and opinion, which both belong to it as a faculty. But 'understanding' means here an infallible, immediate and intuitive grasp of such intelligible objects as the first principles of knowledge; while 'scientific knowledge' means certain knowledge obtained by rational investigation; and 'opinion' means a knowing that falls short of scientific certainty.

             § 640. And in calling imagination one of these 'dispositions or powers' he implies that the cognitive factors here mentioned are either habits or powers. As to these four factors being the only principles of cognition known to the early philosophers, our evidence is the theory of Plato who reduced only these four to numbers--understanding to 1, science to 2, opinion to 3, sense to 4.

             § 641. Next, when he says 'That it is not', he distinguishes imagination from all the above four: first of all from sensation, then from understanding and science, and finally from opinion. As to sensation, he begins by proving that imagination is not one of the senses, either potentially or actually. For imagination is active during sleep. This cannot be due to any sense as in potency, in which state the senses are aware of nothing at all; nor to any sense as in act, for in sleep the senses are not in act. Therefore imagination is neither a sense in potency nor a sense in act.

             § 642. Then, at 'Further etc.', he argues as follows to show that imagination is not a sense in potency. The latter is always found in animals, but imagination, which implies an awareness of appearances, is sometimes lacking. Therefore . . .

             § 643. Then, at 'But if etc.', he gives four reasons for distinguishing imagination from the senses as in act. (1) Sense as in act is found in all animals, i.e. irrational animals; so that if it were the same as imagination, this would be found in all irrational animals, which in fact is not true; for neither ants, nor bees, nor worms have imagination. Therefore . . .

             § 644. But note that all animals have imagination in some sense of the term; but the lower animals have it indeterminately, as Aristotle will explain later. And if ants and bees seem to differ in this respect from the rest of the lower animals, through their apparent exercise of a great deal of intelligence, the truth is, nevertheless, that ants and bees behave so cleverly, not because they are aware of definite images distinct from exterior sensations, but by a natural instinct; for they only imagine so long as they are actually receiving sensible impressions. Their purposeful and, as it were, provident activities do not arise from any image of what is going to happen in the future; their present activities alone are represented inwardly to them, and it is a natural instinct rather than any distinct apprehension which orders these activities to an end. On the other hand, says Aristotle, those animals have imagination in the precise sense of the term which retain a distinct image of things even while they are not actually sensing things.

             § 645. (2) This argument begins at 'Again, sensations'. The senses in the act of sensing are always truthful; they cannot err about their proper objects. But phantasms are very often deceptive, when there is nothing real that corresponds to them. Therefore the imagination is distinct from every sense as in act.

             § 646. (3) This argument comes at 'Again, we do not say'. When we are moved by an actual sense-experience to act immediately and without hesitation, we never say e.g. 'That seems to us a man'. We are more likely to speak thus when we are uncertain, as when we see things at a distance or in the dark. And in these cases the actual sensation is either true or false. For the senses (whatever sense it is which makes us aware of a man) are indeed sometimes deceived as to their indirect object. He adds this in order to show the affinity between imagination, which can also be either truthful or deceptive, and obscure sensations. But as soon as we are sure that we are only imagining, we say 'it appears to be a man', and that we do not know for certain that it is a man. Therefore imagination is distinct from any sense as in act.

             § 647. (4) Again, phantasms come during sleep when the senses are not in act. Therefore a phantasm is not an actual sensation.

             § 648. Next, when he says 'And it is certainly', he shows the difference between imagination and both simple understanding and science. Simple understanding bears upon first principles, and science upon demonstrated conclusions; and these are always true. But images are often false; therefore imagination is neither simple understanding nor science.

             § 649. Then at 'It remains', he shows that imagination is not opinion (which it might seem to be, for opinion too is sometimes false) by two arguments. (1) The result of opinion is belief, if it is natural to believe in one's opinions. If belief is not found in brute animals, this is because they have no opinions. But many brute animals, as he has said, have imagination. Therefore imagination is not opinion.

             § 650. (2) (At, 'Further, belief etc.') Belief always follows opinion (as we have said) because one naturally believes in one's opinions. And the state of being persuaded is the outcome of belief; we believe those things of which we are persuaded. Now persuasion is always accompanied by rational inference, for one must have some reason for being persuaded of anything; hence from first to last reasoning goes along with opinion. But while some brute animals have imaginations, none of them have reason. Imagination, then, is distinct from opinion. Obviously, this argument confirms what the previous one assumes, i.e. that brute animals lack belief.

             § 651. Then at 'It is therefore evident', he shows that imagination is not a combination of any of the factors mentioned above; and more particularly that it is not, as it might rather plausibly seem to be, a combination of sensation and opinion. And here he does three things. First, he states his conclusion, as a further inference from what has been said: that since imagination is neither one of the senses nor opinion, we can already see that it is neither opinion plus sensation--i.e. an opinion essentially, but with a concomitant sensation; nor opinion through sensation--i.e. an opinion essentially, but caused by sensation; nor a mixture of the two, as though both were of its essence. He does not say that imagination is not sensation plus opinion, because it has apparently more to do with opinion, which can be false, than with sensation which is always true.

             § 652. Secondly, at 'And it is clear', he shows what the term opinion would mean if it were true that imagination were a blend of sensation and opinion. For since an image is always of some definite thing, and of nothing else at the same time, then clearly the opinion which, conjoined to sensation, was an act of imagination, would bear simply and solely upon the one object presented to it by the sensation. It is as if one were to say, e.g. that imagination combined an opinion of whiteness and a sense of whiteness; it could not combine an opinion of whiteness and a sense of goodness; for, in that case, the object imagined would not be one and the same. Therefore, if to imagine is to combine opinion and sensation, to be aware of images is simply and solely to have as the object of one's opinion the direct object of a sensation; not in any way the indirect object of that sensation.

             § 653. Thirdly, at 'False appearances', he refutes the above hypothesis. For it can happen that images derived from sensation present us with falsehoods of which, none the less, we form a true opinion. Thus our senses tell us that the sun measures only one foot across; which is false. But by our true opinion we believe that it is larger than 'the inhabited world', i.e. than the whole of our earth. Yet on the hypothesis that the image-appearances are only an opinion conjoined to sensation, one of two consequences must follow. The first is that in the act of conjoining opinion and sensation we reject the true opinion which we held till then, while the thing itself, of which we form our opinion, 'remains', i.e. stays exactly the same; and we ourselves neither forget nor cease to be persuaded of that true opinion. But this is impossible; for there are only three ways in which a true opinion, once held, can be lost: (a) When the object itself changes,--as when we truly opine that Socrates is seated while he is seated; but if, when he ceases to sit, we retain that opinion, it changes from being a true opinion to being false; (b) When we cease to hold an opinion we once held because we forget it; and (c) When we cease to hold an opinion we once held because, for some new reason, we cease from thinking it to be true. It is impossible to lose an opinion if none of these conditions is realised; and yet this is what the first alternative involves.

             § 654. And there is only one other conceivable alternative; which is that the true opinion is retained along with the false one; which would mean that, since the image-appearance is identical with opinion (as it must be if imagining is opining), the same image-appearance is both true and false. And if from being true it becomes false then the 'transformation' of the object, i.e. its alteration from what it was before, must be hidden from him who holds the opinion; otherwise, as soon as the object altered the opinion would alter too, and thus would not be false. He adds this to explain his earlier remark, about the 'remaining' of the object. And his conclusion is that imagination is neither one of the aforesaid four factors in cognition, nor any combination of them.

428b 10-429a 9

IMAGINATION

WHAT IT IS

             BUT SINCE IT CAN HAPPEN THAT, ONE THING moving, another is moved by it; and imagination seems to be a movement, and to arise only with sensation, and in sentient beings, and to be of such objects as are sensed; and since a motion may be caused by actual sensation, and such necessarily resembles sensation,--then imagination will be just this movement, never originated apart from sensation, incapable of existing in non-sentient beings, and enabling its possessor to act and to be affected in many ways, and being itself both true and false.§§ 655-9

             This happens because sense-perception is true of its own proper objects, or has the least possible amount of falsehood; but secondarily it bears on that in which these qualities inhere, and here it can be deceived. Sensation is reliable as to whether a thing is white or not, but not as to whether it is this or that. Thirdly, there are the common qualities consequent on the accidents in which the proper qualities inhere. I mean, such as movement and dimension, which belong to sense-objects--and about these deception very easily arises in sensing. The movement derived from actual sensation differs from the sensations by which these three objects are perceived. Although the first [movement] is true, the sensation itself being present, the others can easily be false, whether sensation be present or not, and especially when the sense-object is distant. If, therefore, nothing except imagination possesses what has been described, then the statement is true, namely that imagination is a movement produced by sensation actuated.§§ 660-7

             Since sight is the most prominent sense, [imagination] has taken its name from light, as there is no seeing without light.§ 668

             And since these images dwell within, and resemble sense experiences, animals do many things in accordance with them; some animals, as lacking reason, namely beasts; but some, i.e. men, when their intellect is veiled either by passion, or by sickness, or by sleep.

             Let so much suffice, therefore, on imagination, its nature and its function.§§ 669-70