It has been customary, since Kant's time, to assert that Cognition, Volition, and Feeling are three fundamentally distinct attitudes of the mind towards reality. They are three distinct ways of experiencing, and each of them informs us of a distinct aspect under which reality may be considered. The Epistemological method of approaching Metaphysics rests on the assumption that by considering what is implied in Cognition—what is its ideal—we may discover what properties the world must have, if it is to be true. And similarly it is held that by considering what is implied in the fact of Willing or Feeling—what is the ideal which they presuppose—we may discover what properties the world must have, if it is to be good or beautiful. The orthodox Idealistic Epistemologist differs from the Sensationalist or Empiricist in holding that what we directly cognise is neither all true nor yet the whole truth: in order to reject the false and to discover further truths we must, he says, not take cognition merely as it presents itself, but discover what is implied in it. And similarly the orthodox Metaphysical Ethicist differs from the mere Naturalist, in holding that not everything which we actually will is good, nor, if good, completely good: what is really good is that which is implied in the essential nature of will. Others again think that Feeling, and not Will, is the fundamental datum for Ethics. But, in either case, it is agreed that Ethics has some relation to Will or Feeling which it has not to Cognition, and which other objects of study have to Cognition. Will or Feeling, on the one hand, and Cognition, on the other, are regarded as in some sense co-ordinate sources of philosophical knowledge—the one of Practical, the other of Theoretical Philosophy. (§ 78 ¶ 1)

What, that is true, can possibly be meant by this view? (§ 78 ¶ 2)