‎COURNOT (A.A.)‎
‎Exposition de la théorie des chances et des probabilités -- EDITION ORIGINALE -- BEL EXEMPLAIRE BIEN COMPLET DE SA PLANCHE DEPLIANTE‎

‎P., Hachette, 1843, un volume in 8 relié en demi-percaline bordeaux (reliure de l'époque), (quelques rousseurs), (2), 8pp., 448pp., 1 PLANCHE DEPLIANTE‎

Reference : 1379

‎---- EDITION ORIGINALE -- BEL EXEMPLAIRE BIEN COMPLET DE SA PLANCHE DEPLIANTE ---- "Cournot's work on the "theory of chance occurences" is important in the history of the calculus of probability, since it examines in an original way the interpretation and foundations of this calculus and its applications. According to Cournot, occurences in our world are always determined by a cause. But in the universe there are independent causal chains. If, at a given point in time and space, two of these chains have a common link, this coincidence constitutes the fortuitous character of the event thus engendered. Consequently, there would be an objective chance occurence that would nevertheless have a cause. This seeming paradox would be no reflection of our ignorance. This objective occurence is assigned a certain value in a case where it is possible to enumerate - for a given event - all the possible combinations of circumstances and all those in which the event occurs. This value is to be interpreted as a degree of "physical possibility". However, one must distinguish between a physical possibility that differs form O (or 1) only by an infinitely small amount and a strict logical impossibility (or necessity). On the other hand, Cournot also insisted on the necessary distinction between this physical possibility or "objective probability" and the "subjective probability" that depends on our ignorance and rest on the consideration of events that are deemed equiprobable since there is not sufficient cause to decide otherwise... To these two ideas of probability Cournot added a third that he defined as "philosophical probability". This is the degree of rational, not measurable, belief that we accord a given scientific hypothesis... Cournot had the distinction of having been the first to dissociate - in a radical way - various ideas that still were obscure, thus opening the way for deeper and more systematic research by more exact mathematicians. He also was able to show clearly the importance of the applications of the calculus of probability to the scientific description and explanation of human acts. He himself - following Condorcet and Poisson - attempted to interpret legal statistics. But he also warned against "premature and abusive applications" that might discredit this ambitions project...". (DSB III pp. 450/454)**1379/ARM1D‎