He criticised at once the three doctrines of poetry as a means of adorning and communicating intellectual truth, as merely subservient to pleasure, and as a harmless mental exercise for those who can do it. Poetry is not esoteric wisdom: it does not presuppose the logic of the intellect: it does not contain philosophical judgments. The philosophers, in finding these things in poetry, have simply put them there themselves without realising it. Poetry is produced not by the mere caprice of pleasure, but by natural necessity. It is so far from being superfluous and capable of elimination, that without it thought cannot arise: it is the primary activity of the human mind. Man, before he has arrived at the stage of forming universals, forms imaginary ideas. Before he reflects with a clear mind, he apprehends with faculties confused and disturbed: before he can articulate, he sings: before speaking in prose, he speaks in verse: before using technical terms, he uses metaphors, and the metaphorical use of words is as natural to him as that which we call "natural." So far from being a fashion of expounding metaphysics poetry is distinct from and opposed to metaphysics. The one frees the intellect from the senses, the other submerges and overwhelms it in them: the one reaches perfection in proportion as it rises to universality, the other, as it confines itself to the particular: the one enfeebles the imagination, the other strengthens it. The one takes precautions against turning the mind into body, the other delights in giving body to the mind. The judgments of poetry are composed of sense and emotion, those of philosophy are composed of reflection, which if introduced into poetry makes it frigid and unreal: and no one in the whole course of history has ever been at once a great poet and a great metaphysician. Poets and philosophers may be called respectively the senses and the intellect of mankind: and in this sense we may retain as true the scholastic saying "there is nothing in the intellect which was not first in the senses." Without sense, we cannot have intellect: without poetry, we cannot have philosophy, nor indeed any civilisation.