A characteristic position in Schopenhauer's theory of knowledge, and one that is constantly finding new expression in his writings, is the distinction between abstract and intuitive knowledge already touched on. Intuitive knowledge of the kind that is common to men and animals, as we have seen, makes up, in his terminology, the 'understanding'; while 'reason' is the distinctively human faculty of concepts. When he depreciates this, as he often does, in comparison with 'intuition,' it must be remembered that he does not limit this term to perception of particulars, but ascribes to what he calls the 'Platonic Idea' a certain kind of union between reason and 'phantasy,' which gives it an intuitive character of its own. Thus intuition can stand, though not in every case for what is higher, yet always for that which is wider and greater and more immediate. Whatever may be done with reflective reason and its abstractions, every effectual process of thought must end, alike for knowledge and art and virtue, in some intuitive presentation. The importance of reason for practice is due to its generality. Its function is subordinate. It does not furnish the ground of virtuous action any more than aesthetic precepts can enable any one to produce a work of art; but it can help to preserve constancy to certain maxims, as also in art a reasoned plan is necessary because the inspiration of genius is not every moment at command. Virtue and artistic genius alike, however, depend ultimately on intuition: and so also does every true discovery in science. The nature of pedantry is to try to be guided everywhere by concepts, and to trust nothing to perception in the particular case. Philosophy also Schopenhauer regards as depending ultimately on a certain intuitive view; but he allows that it has to translate this into abstractions. Its problem is to express the _what_ of the world in abstract form: science dealing only with the _why_ of phenomena related within the world. This character of philosophy as a system of abstract concepts deprives it of the immediate attractiveness of art; so that, as he says in one place, it is more fortunate to be a poet than a philosopher. CHAPTER III METAPHYSICS OF THE WILL We have seen that scientific explanation does not go beyond presentations ordered in space and time. This is just as true of the sciences of causation--the 'aetiological' sciences--as it is of mathematical science. All that we learn from Mechanics, Physics, Chemistry and Physiology, is 'how, in accordance with an infallible rule, one determinate state of matter necessarily follows another: how a determinate change necessarily conditions and brings on another determinate change.' This knowledge does not satisfy us. We wish to learn the significance of phenomena; but we find that from outside, while we view them as presentations, their inner meaning is for ever inaccessible.