for instance, Einstein's equations (supposing them to be correct) will give you the answer to any question you can possibly ask about gravitation - you certainly cannot expect more than this, you cannot expect answers to impossible, senseless questions. And a question aiming at the "internal" nature of gravitation, as opposed to its properties as they reveal themselves in the equations (which purely formal, of course) would be senseless.
There is no meaning in any distinction between the "inner" and the "outward" nature of things. The best expression of the "nature of electricity" are the equations of the theoretical physicist: it would be ridiculous to think of replacing them by some immediate intuition; no one can seriously believe that a person experiencing an electric shock had really a better knowledge of the essence of electricity than Maxwell and his modern followers.
This point must be especially insisted upon, as there seems to be a certain lack of clarity in this respect even in the writings of some of the most enlightened thinkers who are otherwise perfectly well aware of the all—importance of form and structure for scientific knowledge. Bertrand Russell, certainly one of the greatest living authorities on the nature of science has written in his "Introduction to mathematical Philosophy" (2nd ed. p. 55) : "We know that certain scientific propositions [...] are more or less true of the world, but we are very much at sea as to the interpretation to be put upon the terms which occur in these propositions. We know much more (to use, for a moment, an old-fashioned pair of terms) about the form of nature than about the matter." The word "matter" seems to be used here in the same sense in which we have used the word "content"; and if this is so, Russell's statement surely stands in need of correction. It will not do to say that we know very little about the content of nature and to speak as if this were a regrettable but perhaps not altogether hopeless state of affairs: no, it is self-contradictory to speak of "knowledge of the content of nature"; such a phrase is devoid of meaning. A few pages further on, where Russell is concerned with different possibilities of interpretation for one and the same formal structure, he seems to be on the right track when he writes (p. 61): "[...] the only difference must be in just that essence of individuality which always eludes words and baffles description, but which, for that very reason, is irrelevant to science." Can this mean that science is not interested in content, but that it is very important in all other respects, for instance
