is? By no means! In order to give a name to the colour I am seeing I have to go beyond the immediacy of pure intuition, I have to think, be it ever so little. I have to recognise the colour as that particular one I was taught to call "blue". This involves an act of comparison, or association; to call a thing by its proper name is an intellectual act — the very simplest act of the intellect, to be sure — and its result is real knowledge in the proper sense in which we use the word. The sentence "this is blue" expresses real knowledge, not explanatory but factual knowledge.
The simple descriptive knowledge "this is blue" gives rise to an explanation replacing the term "blue" by a complex of other terms: a rather difficult task, which is undertaken by physics (or physiology) and leads to a proposition of the form: "this blue is light of the intensity so — and — so, the wave — length so — and — so!", and so on (or "this blue corresponds to such — and — such a process of such — and — such a nervous system"). All this confirms our statement that knowledge does not require a real intimacy between the knower and the known and that the most perfect knowledge does not consist in a union of both. On the contrary, all knowledge seems to become more and more complete the farther we move away from the object. Think of how perfect our knowledge of the nature of matter is at the present time — at least compared with former times — and how utterly remote it is from what people thought they knew about matter by intuition ! If we ask the scientist about the nature of water he tells us that it consists of molecules composed of two atoms of hydrogen and one atom of oxygen, and that these atoms consist of protons and electrons in very definite numbers and arrangements, and that protons and electrons are nothing but a certain way of speaking of frequencies of vibrations, probabilities, and so on, thus substituting for the word "water" other terms with extremely strange meanings far, far away from anything with which we are directly acquainted and showing no similarity with the intuitions that arise when we are on intimate terms with water (e.g. when drinking it or bathing in it). The scientist arrives at his results in an exceedingly roundabout way, and we accept them as the true answer to our question concerning the real nature of water. Could we also accept the answer of the metaphysician? He tells us that the result of the scientist does not satisfy him, because it gives a description of water in terms of something else, contemplating it merely
