Isolated facts and experiments have in themselves no value, however great their number may be. They only become valuable in a theoretical or practical point of view when they make us acquainted with the law of a series of uniformly recurring phenomena, or, it may be, only give a negative result showing an incompleteness in our knowledge of such a law, till then held to be perfect.
Hermann von HelmholtzWhat we see is the solution to a computational problem, our brains compute the most likely causes from the photon absorptions within our eyes.
Hermann von HelmholtzEach individual fact, taken by itself, can indeed arouse our curiosity or our astonishment, or be useful to us in its practical applications.
Hermann von HelmholtzThe most startling result of Faraday's Law is perhaps this. If we accept the hypothesis that the elementary substances are composed of atoms, we cannot avoid concluding that electricity also, positive as well as negative, is divided into definite elementary portions, which behave like atoms of electricity.
Hermann von HelmholtzJust as a physicist has to examine the telescope and galvanometer with which he is working; has to get a clear conception of what he can attain with them, and how they may deceive him; so, too, it seemed to me necessary to investigate likewise the capabilities of our power of thought.
Hermann von Helmholtz