4. Hear now how that which disquiets your mind may disquiet it no more. The mode of existence (Species—the second of the three above named) which is properly ascribed to the Son, has to do with training, and with a certain art, if I may use that word in regard to such things, and with the exercise of intellect, by which the mind itself is moulded in its thoughts upon things. Therefore, since by that assumption of human nature the work accomplished was the effective presentation to us of a certain training in the right way of living, and exemplification of that which is commanded, under the majesty and perspicuousness of certain sentences, it is not without reason that all this is ascribed to the Son. For in many things which I leave your own reflection and prudence to suggest, although the constituent elements be many, some one nevertheless stands out above the rest, and therefore not unreasonably claims a right of possession, as it were, of the whole for itself: as, e.g., in the three kinds of questions above mentioned, although the question raised be whether a thing is or not, this involves necessarily also both what it is (this or that), for of course it cannot be at all unless it be something, and whether it ought to be approved of or disapproved of, for whatever is is a fit subject for some opinion as to its quality; in like manner, when the question raised is what a thing is, this necessarily involves both that it is, and that its quality may be tried by some standard; and in the same way, when the question raised is what is the quality of a thing, this necessarily involves that that thing is, and is something, since all things are inseparably joined to themselves;—nevertheless, the question in each of the above cases takes its name not from all the three, but from the special point towards which the inquirer directed his attention. Now there is a certain training necessary for men, by which they might be instructed and formed after some model. We cannot say, however, regarding that which is accomplished in men by this training, either that it does not exist, or that it is not a thing to be desired [i.e. we cannot say what it is, without involving an affirmation both of its existence and of its quality]; but we seek first to know what it is, for in knowing this we know that by which we may infer that it is something, and in which we may remain. Therefore the first thing necessary was, that a certain rule and pattern of training be plainly exhibited; and this was done by the divinely appointed method of the Incarnation, which is properly to be ascribed to the Son, in order that from it should follow both our knowledge, through the Son, of the Father Himself, i.e. of the one first principle whence all things have their being, and a certain inward and ineffable charm and sweetness of remaining in that knowledge, and of despising all mortal things,—a gift and work which is properly ascribed to the Holy Spirit. Wherefore, although in all things the Divine Persons act perfectly in common, and without possibility of separation, nevertheless their operations behoved to be exhibited in such a way as to be distinguished from each other, on account of the weakness which is in us, who have fallen from unity into variety. For no one ever succeeds in raising another to the height on which he himself stands, unless he stoop somewhat towards the level which that other occupies.