On The Subject of Intellect

I have taken note that you ask that a brief discussion of the intellect [and the object of comprehension], according to the theory of Plato and Aristotle, be communicated to you. Their theory is that intellect falls into four types. The first is the intellect which is always active; the second is the intellect potentially in the mind; the third is the intellect when it becomes an efficient agent by virtue of [its] power in the mind; the fourth is the intellect which we call demonstrative, and it is this intellect which Aristotle approximates to sensation, because of the propinquity of sensation to truth and because it is in complete communion with it.

For Aristotle has said that there are two kinds of form. One of them has matter and it is that which underlies sensation; but the other is that which is devoid of matter and is that which forms the substratum of intellect. Indeed, the former has to do with things, while the latter is above that.

Now, the form that resides in matter, is actually perceived; for if it were not actually perceived it would not lie within the range of sensation. Now, if the mind apprehends it, then it is as such in the mind. But it does not apprehend it unless it was first potentially in the mind. Therefore, when the mind apprehends it, it becomes actual in the mind. However, it is not in the mind as something is in a vase, nor does it chase through the body; for the mind is not the body, nor is it limited. Therefore, it is in the mind, and the mind is one, identical with itself, and not anything other than itself; nor is it again different by virtue of a twisting of terms

Similarly, the faculty of feeling does not exist except in the soul. But it is not part of the soul as a member is part of the body; rather, it is the soul itself, and as such is feeling. Likewise, the form of the sense datum is not in the mind as something distinct or different. Therefore, as Aristotle has declared, the sense datum in the mind is the perceiving agent in conformity to what is in the mind. But, the sense datum as a material thing is outside the perceiving mind. Now, therefore, that which is in matter is the sense datum, not the perceiving agent.

Similarly, Aristotle has explained intelligence as the mind when it apprehends the object of comprehension, or THE form which has neither matter nor sensuous representation and is one with mind, and is then in actuality in the mind; for it was not previously in actuality, but [only] potentially in the mind. This form, therefore, which hasn't any matter or sensuous representation as yet, is the intellect which the mind has attained through primal intelligence, the concept of all, ever active. However, this does not become contributive, unless the mind has attained the power to receive it, since the mind is [only] potentially an agent of intelligence, whereas primal intelligence is always active. For nothing assimilates anything through its own receptivity except that which belonged to it potentially and not in actuality. Nothing, to be sure, that a thing possesses potentially works as an efficient cause by itself; for if it were self-existent, it would always be in activity; since its essence would always be its own and spontaneous. Therefore, nothing that exists potentially becomes an efficient cause unless by virtue of something that is an efficient cause. Hence, the mind is potentially an agent of intelligence, yet it becomes an efficient cause at the instigation of primal intelligence, looking to which it becomes an agent of intelligence in actuality. And, when an intelligible form is conjoined with it, it is not one thing, and the intelligible form another, because it is not divisible, allowing it to be changed. But when a union is brought about with the intelligible form, then it and the intellect are one, if you will allow the agent of intelligence and that which is comprehended. Thus, the intellect and the object of comprehension are one when they exist in the mind. In truth, the intellect as such, which is always active and draws forth the mind so it may become an agent of intelligence in fact, after it was potentially intelligent, and the object of comprehension as such are not one and the same thing. Therefore, the object of comprehension in the mind and the first type of intellect derived from primal intelligence are not the same; however, the intellect derived from the mind and the object of comprehension are one and the same.

But the intellect, which in simplicity is more like the soul, is much higher in comparison with the thing comprehended than sensation, as compared with the sense datum. The first type of intellect, therefore, is the cause of all that is comprehended. But the second type of intellect is potentially in the mind.

Intellect is, thus, either of the first type in that it is for all that is comprehended, or it is of the second type and then it is potentially in the mind; at all events, the mind is not an actual agent of intelligence. The third type of intellect, however, is the one that is working efficiently in the mind which has already acquired it. And, it is kept there in such a manner that, when it wills, it may use it and cause it to be in one other than itself. In the same way, writing is ready and easy for a scribe because he has already become proficient in it and it has become second nature to him. Consequently, he communicates and practices it whenever he is so inclined. The fourth type of intellect is that which goes forth from the mind which, when you desire to communicate it, will work an effect in someone other than yourself.

The second type of intellect derives, therefore, from the the third and fourth, for the reason that the third is an acquisition of the mind and causes it to appear whenever it wishes, either at the first instance of its acquisition in us, or in the second instance of its appearance outside us. Then the mind uses it. Therefore, the third is the one that is an acquisition of the mind, which is prior to it, and, if it so wills, becomes spontaneous in it. But the fourth is that which appears to work as an efficient cause from the mind.

These are, therefore, the parts into which the foremost philosophers have divided the intellect. May this explanation suffice for what you had in mind.

... The Book of Alkindi on the Subject of Intellect, al-Kindi