…The vast majority of scientists, both generally and in this special branch of science in question, viz., physics, are invariably on the side of materialism. A minority of new physicists, however, influenced by the break-down of old theories brought about by the great discoveries of recent years, influenced by the crisis in the new physics, which has very clearly revealed the relativity of our knowledge, have, owing to their ignorance of dialectics, slipped into idealism by way of relativism. The physical idealism in vogue today is as reactionary and transitory an infatuation as was the fashionable physiological idealism of the recent past.
…behind the epistemological scholasticism of empirio-criticism one must not fail to see the struggle of parties in philosophy, a struggle which in the last analysis reflects the tendencies and ideology of the antagonistic classes in modern society. Recent philosophy is as partisan as was philosophy two thousand years ago. The contending parties are essentially, although this is concealed by a pseudo-erudite quackery of new terms or by a weak-minded non-partisanship – materialism and idealism. The latter is merely a subtle, refined form of fideism, which stands fully armed, commands vast organisations and steadily continues to exercise influence on the masses, turning the slightest vacillation in philosophical thought to its own advantage. The objective, class role of empirio-criticism consists entirely in rendering faithful service to the fideists in their struggle against materialism in general and historical materialism in particular.
V.I.Lenin, Materialism and Empirio-criticism: Critical Comments on a Reactionary Philosophy, Progress Publishers, Moscow, 1975, 335-336
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