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Physical Science and Philosophy: Prof. P. A. M. Dirac, F.R.S., St. John's College, Cambridge


IN his article in NATURE of May 8, Dr. H. Dingle criticizes my letter to NATURE of February 20, on the grounds that it departs from the Galilean scientific method of building up theory to fit observations. The successful development of science requires a proper balance to be maintained between the method of building up from observations and the method of deducing by pure reasoning from speculative assumptions, and I think my letter satisfies this condition; but as it was written rather concisely, I would like here to restate the main points of the argument in a form which brings its observational basis to the forefront, and is essentially independent of cosmological theory.

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Physical Science and Philosophy: Prof. P. A. M. Dirac, F.R.S., St. John's College, Cambridge. Nature 139, 1001–1002 (1937).

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