Just 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 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 HelmholtzWhoever, in the pursuit of science, seeks after immediate practical utility, may generally rest assured that he will seek in vain.
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 total quantity of all the forces capable of work in the whole universe remains eternal and unchanged throughout all their changes. All change in nature amounts to this, that force can change its form and locality, without its quantity being changed. The universe possesses, once for all, a store of force which is not altered by any change of phenomena, can neither be increased nor diminished, and which maintains any change which takes place on it.
Hermann von Helmholtz