The 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 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 HelmholtzNot that I wish by any means to deny, that the mental life of individuals and peoples is also in conformity with law, as is the object of philosophical, philological, historical, moral, and social sciences to establish.
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 HelmholtzIsolated 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 Helmholtz