=1967.= The theory in question [theory of probability] affords an excellent illustration of the application of the theory of permutation and combinations which is the fundamental part of the algebra of discrete quantity; it forms in the elementary parts an excellent logical exercise in the accurate use of terms and in the nice discrimination of shades of meaning; and, above all, it enters into the regulation of some of the most important practical concerns of modern life.--CHRYSTAL, GEORGE. _Algebra, Vol. 2 (Edinburgh, 1889), chap. 36, sect. 1._ =1968.= There is possibly no branch of mathematics at once so interesting, so bewildering, and of so great practical importance as the theory of probabilities. Its history reveals both the wonders that can be accomplished and the bounds that cannot be transcended by mathematical science. It is the link between rigid deduction and the vast field of inductive science. A complete theory of probabilities would be the complete theory of the formation of belief. It is certainly a pity then, that, to quote M. Bertrand, “one cannot well understand the calculus of probabilities without having read Laplace’s work,” and that “one cannot read Laplace’s work without having prepared oneself for it by the most profound mathematical studies.”--DAVIS, E. W. _Bulletin American Mathematical Society, Vol. 1 (1894-1895), p. 16._ =1969.= The most important questions of life are, for the most part, really only problems of probability. Strictly speaking one may even say that nearly all our knowledge is problematical; and in the small number of things which we are able to know with certainty, even in the mathematical sciences themselves, induction and analogy, the principal means for discovering truth, are based on probabilities, so that the entire system of human knowledge is connected with this theory.--LAPLACE. _Théorie Analytique des Probabilitiés, Introduction; Oeuvres, t. 7 (Paris, 1886), p. 5._ =1970.= There is no more remarkable feature in the mathematical theory of probability than the manner in which it has been found to harmonize with, and justify, the conclusions to which mankind have been led, not by reasoning, but by instinct and experience, both of the individual and of the race. At the same time it has corrected, extended, and invested them with a definiteness and precision of which these crude, though sound, appreciations of common sense were till then devoid.--CROFTON, M. W. _Encyclopedia Britannica, 9th Edition; Article “Probability.”_ =1971.= It is remarkable that a science [probabilities] which began with the consideration of games of chance, should have become the most important object of human knowledge.--LAPLACE.