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 intentionally, but due to exceptional concurrences of circumstances.

The phenomena of nature are a system of things which co-exist and follow each other according to invariable laws. This deadly proposition was asserted early in the nineteenth century to be an axiom of science. It was formulated by Mill (in his System of Logic, 1843) as the foundation on which scientific induction rests. It means that at any moment the state of the whole universe is the effect of its state at the preceding moment; the casualcausal [sic] sequence between two successive states is not broken by any arbitrary interference suppressing or altering the relation between cause and effect. Some ancient Greek philosophers were convinced of this principle; the work done by modern science in every field seems to be a verification of it. But it need not be stated in such an absolute form. Recently, scientific men have been inclined to express the axiom with more reserve and less dogmatically. They are prepared to recognize that it is simply a postulate without which the scientific comprehension of the universe would be impossible, and they are inclined to state it not as a law of causation—for the idea of causation leads into metaphysics—but rather as uniformity of experience. But they are not