'The renouncing of life and immediacy, which was the premise for the progress of natural science since Newton, formed the real basis for the bitter struggle which Goethe waged against the physical optics of Newton. It would be superficial to dismiss this struggle as unimportant: there is much significance in one of the most outstanding men directing all his efforts to fighting against the development of Newtonian optics.' There is only one thing for which Heisenberg criticizes Goethe: 'If one should wish to reproach Goethe, it could only be for not going far enough - that is, for having attacked the views of Newton instead of declaring that the whole of Newtonian Physics-Optics, Mechanics and the Law of Gravitation - were from the devil.' Although the full significance of Heisenberg's remarks on Goethe will become apparent only at a later stage of our discussion, they have been quoted here because they form part of the symptom we wish to characterize. Only this much may be pointed out immediately, that Goethe - if not in the scientific then indeed in the poetical part of his writings - did fulfil what Heisenberg rightly feels to have been his true task.2 We mentioned Heisenberg's speech as a symptom of a certain tendency, characteristic of the latest phase in science, to survey critically its own epistemological foundations. A few years previous to Heisenberg's speech, the need of such a survey found an eloquent advocate in the late Professor A. N. Whitehead, in his book Science and the Modern World, where, in view of the contradictory nature of modern physical theories, he insists that 'if science is not to degenerate into a medley of ad hoc hypotheses, it must become philosophical and enter upon a thorough criticism of its own foundations'. Among the scientists who have felt this need, and who have taken pains to fulfil it, the late Professor A. Eddington obtains an eminent position. Among his relevant utterances we will quote here the following, because it contains a concrete statement concerning the field of external observation which forms the basis for the modern scientific world-picture. In his Philosophy of Physical Science we find him stating that 'ideally, all our knowledge of the universe could have been reached by visual sensation alone - in fact by the simplest form of visual sensation, colourless and non-stereoscopic'.3 In other words, in order to obtain scientific cognition of the physical world, man has felt constrained to surrender the use of all his senses except the sense of sight, and to limit even the act of seeing to the use of a single, colour-blind eye.