You are acquainted with the well-known principle of the philosophers that God is the intellectus, the ens intelligens, and the ens intelligibile. These three things are in God one and the same, and do not in any way constitute a plurality. We have also mentioned it in our larger work, “Mishneh Torah,” and we have explained there that it is a fundamental principle of our religion, namely, that He is absolutely one, that nothing combines with Him; that is to say, there is no Eternal thing besides Him. On that account we say ḥai adonay, “the Lord liveth” (Ruth iii. 13), and not ḥe adonay, “the life of the Lord,” for His life is not a thing distinct from His essence, as we have explained in treating of the inadmissibility of the attributes. There is no doubt that he who has not studied any works on mental philosophy, who has not comprehended the nature of the mind, who has no knowledge of its essence, and considers it in no other way than he would consider the nature of whiteness and of blackness, will find this subject extremely difficult, and to him our principle that the intellectus, the intelligens, and the intelligibile, are in God one and the same thing, will appear as unintelligible as if we said that the whiteness, the whitening substance, and the material which is whitened are one and the same thing. And, indeed, many ignorant people refute at once our principle by using such comparisons. Even amongst those who imagine that they are wise, many find this subject difficult, and are of opinion that it is impossible for the mind to grasp the truth of this proposition, although it is a demonstrated truth, as has been shown by Metaphysicians. I will tell you now what has been proved. Man, before comprehending a thing, comprehends it in potentia (δυνάμει); when, however, he comprehends a thing, e.g., the form of a certain tree which is pointed out to him, when he abstracts its form from its substance, and reproduces the abstract form, an act performed by the intellect, he comprehends in reality (ἐνεργείᾳ), and the intellect which he has acquired in actuality, is the abstract form of the tree in man’s mind. For in such a case the intellect is not a thing distinct from the thing comprehended. It is therefore clear to you that the thing comprehended is the abstract form of the tree, and at the same time it is the intellect in action; and that the intellect and the abstract form of the tree are not two different things, for the intellect in action is nothing but the thing comprehended, and that agent by which the form of the tree has been turned into an intellectual and abstract object, namely, that which comprehends, is undoubtedly the intellect in action. All intellect is identical with its action; the intellect in action is not a thing different from its action, for the true nature and essence of the intellect is comprehension, and you must not think that the intellect in action is a thing existing by itself, separate from