CHAPTER IV
CHAPTER IV
[86] So much for the contention that intellect is not the soul which is the form of our body nor a part of it but some kind of separate substance. There remains to discuss the claim that there is one possible intellect for everybody. There would perhaps be some reason for saying this of agent intellect, and many philosophers do say it, for nothing absurd seems to follow from several things being perfected by one agent, as by one sun the visual powers of all animals are able to see. Although this is not Aristotle’s intention—he holds that the agent intellect is in the soul—he nonetheless compares it to a light, and Plato, holding that the intellect is one separate thing, likened it to the sun, as Themistius tells us, for there is one sun but many lights diffused from it for the sake of seeing. But, however it be with the agent intellect, to say that the possible intellect is one for all men appears impossible in many ways.
[87] First, because if the possible intellect is that whereby we understand, of an individual man who understands it must be said either that he is intellect itself or that intellect formally inheres in him, not indeed in such a way that it be the form of the body but rather a power of the soul which is the form of the body. Should anyone say that the singular man is intellect itself, it would follow that this singular man would not differ from another singular man and that all men are one man, not by sharing in the same species, but as one individual. But if intellect is in us formally, it would follow, as has already been said, that there are different forms of different bodies. For just as man is composed of body and soul, so this man, Callias or Socrates, is composed of this body and this soul. If souls differ, however, and the possible intellect is the power of the soul whereby the soul understands, they must differ numerically, for it is impossible to imagine numerically one power of different things. Should someone say that man understands through possible intellect as by something of his own, which however is not a part of him as a form but rather as a mover, it has already been shown above [79] that on this view it can in no wise be said that Socrates understands.
[88] But let us grant that Socrates understands because the intellect understands although intellect is only a mover, as a man sees because the eye sees. And, to keep to the analogy, let us posit that there is numerically one eye for all men. Now we ask whether all men are one seeing entity or many. To discover the truth of the matter, it should be noted that the first mover differs from the instrument, for if many men use numerically one instrument we say there are many agents, for example, when many use one machine for the throwing of stones or for elevation. If however the chief agent is one, but uses many instruments, there is nonetheless one agent even though many instruments are needed for it, though perhaps a diversity of operations because of the diversity of instruments. Sometimes however there is one operation although many instruments are required for it. The unity of the one acting is read not from the instruments but from the chief agent who uses the instruments.
Thus on the position described earlier, if the eye were what is principal in a man and it would uses all powers of the soul and parts of the body as instruments, many having one eye would be one seeing thing. But if the eye were not what is principal in man, but something higher that uses the eye and is diversified in diverse men, there would indeed be many seeing but with one eye.
[89] But obviously it is intellect that is principal in man and uses all the powers of the soul and bodily members as organs. Hence Aristotle’s careful remark that man is intellect “or especially it.” If then there were one intellect for all, it would necessarily follow that there is only one who understands and consequently only one who wills and of his own free will uses all those things thanks to which men are diverse from one another. From which it follows further that there would be no difference between men as to the free choice of will but it would be the same for all, if indeed intellect, in which resides the principality and dominion of using all the others, is one and undivided in all. But this is clearly false, impossible and repugnant to what is obvious; it destroys the whole of moral science and all those things which pertain to civil interchange, which is natural to man, as Aristotle says.
[90] Again, if all men understand by one intellect, however it be united to them, whether as form or as mover, it necessarily follows that of all men there would be numerically one act of understanding which is both simultaneous and of one intelligible object. For example, if I understand stone and you do likewise, it would be necessary that my intellectual activity and yours be one and the same. The operation of the same active principle, be it form or mover, with respect to the same object at the same time, must be numerically one, as is clear from what the Philosopher says in Book Five of the Physics. So, if there were many men having one eye, the seeing of all with respect to the same object at the same time could only be one.
[91] So too if there were one intellect for all, it would follow that there is but one intellectual operation of all men understanding the same thing at the same time, especially since nothing in terms of which men differ from one another would share in the intellectual operation. For phantasms are preambles to the action of intellect, as colors are to the act of vision, hence the action of intellect would not be diversified because of their differences, especially with regard to one intelligible. They distinguish the knowledge of this one from the knowledge of that one because the one understands those things of which he has phantasms and the other those of which he has phantasms. But when two know and understand the same thing, intellectual activity itself can in no way be diversified by the diversity of phantasms.
[92] Further, it should be pointed out that this position manifestly conflicts with the teaching of Aristotle. For when he says of possible intellect that it is separate and potentially all things, he adds that “When thought has become each thing in the way in which a man who actually knows is said to do so,” that is, in the way that knowledge is an act and the knower is said to be in act insofar as he has the habit, he adds, “this happens when he is now able to exercise the power on his own initiative; its condition is still one of potentiality, but in a different sense from the potentiality which preceded the acquisition of knowledge by learning or discovery.” (429b5-9) Later he asks, “If intellect is simple and impassible and has nothing in common with anything else, as Anaxagoras says, how can it come to think at all if thinking involves a kind of passivity?” (429b23-25) And in reply says, “intellect is in a sense potentially whatever is thinkable, though actually it is nothing until it has thought. What it thinks must be in it just as characters are said to be on a writing-table on which as yet nothing actually stands written: this is exactly what happens with intellect.” (429b30-430a2) It is the teaching of Aristotle, therefore, that the possible intellect is in potency prior to learning or discovery, like a table on which nothing is yet written, but after learning and discovery it is in act by the habit of science, thanks to which it can actuate itself even though it is then in potency to actually considering.
[93] Three things should be noted here. First, that the habit of science is the first act of the possible intellect which, thanks to it, comes to be in act and can operate on its own. Science is not only according to illumined phantasms, as some say, or a faculty which we acquire by frequent meditation and exercise, in order that we might be linked with possible intellect by way of our phantasms. Second, it should be noted that before we learn or discover, the possible intellect itself is in potency as a table on which nothing is written. Third, that through our learning or discovering the possible intellect becomes actual.
[94] None of these things could be if there were only one possible intellect for all who are, were or will be. It is obvious that species are conserved in the intellect, for it is the place of forms, as the Philosopher said above (On the Soul, III, 429127-28); moreover, science is a permanent habit. If then one of the foregoing men becomes actual with respect to some intelligible species and is perfected by the habit of science, that habit and those species remain in him. Since any recipient does not have what it receives, it will be impossible that through my learning or discovering those species be acquired by the possible intellect. For although someone might say that through my discovering the possible intellect can newly come to be in act with respect to something, for example if I should discover some knowable thing never before discovered, yet this could not come about through learning, for I can only learn what the teacher knew. It would therefore be pointless to say that the intellect was in potency prior to learning or discovering.
[95] Were someone to add that, according to the opinion of Aristotle, there have always been men, it would follow that there was never a first man who understood and thus intelligible species are acquired by possible intellect through no one’s phantasms but are intelligible species of an eternal possible intellect. In vain therefore did Aristotle posit an agent intellect to make potentially intelligible things actually intelligible; in vain too did he posit that phantasms are to the possible intellect as colors are to sight, if the possible intellect receives nothing from phantasms. For this too seems irrational that a separated substance should receive from our phantasms and that it cannot understand itself save through our learning or understanding. But Aristotle added to the foregoing, “and it can then understand itself,” (429b9) namely, after learning or discovering.
[96] Should they wish to evade these absurdities by claiming that Aristotle says all those things about the possible intellect insofar as it is made one with us and not as it is in itself, it must first be said that Aristotle’s words do not mean that. Indeed he speaks of the possible intellect in terms of what is proper to it and insofar as it is distinguished from the agent. Then, if no help is forthcoming from Aristotle’s words, let us posit, as they say, that the possible intellect eternally has intelligible species through which it is made one with us according to the phantasms which are in us. It is necessary that the intelligible species which are in the possible intellect and the phantasms that are in us be related in one of three ways. The first is that the intelligible species which are in the possible intellect are taken from the phantasms which are in us, as Aristotle’s words suggest. That this is ruled out by the position under consideration has been shown. The second way is that the species are not taken from phantasms but are shone upon our phantasms, for example, if there were species in the eye shining on the colors which are in the wall. The third way is that the intelligible species are neither received in the possible intellect from the phantasms nor imprint something on the phantasms.
[98] If the second way is taken, namely that the intelligible species illumine the phantasms and in this way are understood, it would follow, first, that the phantasms come to be intelligible in act not through the agent intellect but through the possible intellect and its species. Second, that such an illumination of phantasms could not make phantasms intelligible in act: phantasms do not become intelligible in act except through abstraction; but this would be more like a receiving than an abstracting. Again, since any reception is according to the nature of the receiver, the illumining of the intelligible species which are in the possible intellect will not be of phantasms which are in us in an intelligible mode, but sensibly and materially. Thus we could not understand the universal thanks to this kind of illumination. But if the intelligible species of the possible intellect are neither taken from phantasms nor shone upon them, they will be wholly disparate, having no similarity, and phantasms would have nothing to do with understanding, which flies in the face of the obvious. Thus there is no possible way in which the possible intellect could be one and the same for all men.