id author title date pages extension mime words sentence flesch summary cache txt 35421 Mill, John Stuart A System of Logic: Ratiocinative and Inductive, 7th Edition, Vol. II .txt text/plain 197533 5616 46 When a fact has been observed a certain number of times to be true, and is not in any instance known to be false; if we at once affirm that fact as an universal truth or law of nature, without testing it by any of the four methods of induction, nor deducing it from other known laws, we shall in general err grossly: but we are perfectly justified in affirming it as an empirical law, true within certain limits of time, place, and circumstance, provided the number of coincidences be greater than can with any probability be ascribed to chance. In the present chapter our attention will be directed to a particular case of the derivation of laws from other laws, but a case so general, and so important, as not only to repay, but to require, a separate examination. cache/35421.txt txt/35421.txt