Pierre-Simon Laplace: Probability

“Life's most important questions are, for the most part, nothing but probability problems.”

Pierre-Simon Laplace

citation needed
"Les questions les plus importantes de la vie ne sont en effet, pour la plupart, que des problèmes de probabilité."

Question , Problem , Life , Parting

“The most important questions of life… are indeed for the most part only problems of probability.”

Pierre-Simon Laplace book Philosophical Essay on Probabilities

Philosophical Essay on Probabilities (1902)
Context: The most important questions of life... are indeed for the most part only problems of probability. Strictly speaking it may even be said 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, the principal means for ascertaining truth—induction and analogy—are based on probabilities.<!--p.1

Life , Question , Problem , Parting

“It is to the influence of the opinion of those whom the multitude [the populous] judges best informed, and to whom it has been accustomed to give its confidence in regard to the most important matters of life, that the propagation of those errors is due, which in times of ignorance, have covered the face of the earth. Magic and astrology offer us two great examples. These errors… having for a basis only universal credence, have maintained themselves during a very long time; but at last the progress of science has destroyed them in the minds of enlightened men, whose opinion consequently has caused them to disappear… through the power of imitation and habit which had so generally spread them… This power, the richest resource of the moral world, establishes and conserves in a whole nation ideas entirely contrary to those… elsewhere… What indulgence ought we not then to have for opinions different from ours, when this difference often depends only upon the various points of view where circumstances have placed us! Let us enlighten those whom we judge insufficiently instructed; but first let us examine critically our own opinions, and weigh with impartiality, their respective probabilities.”

Pierre-Simon Laplace book Philosophical Essay on Probabilities

p, 125
Philosophical Essay on Probabilities (1902)

Life , Men , World , Error

“"One sees, from this Essay, that the theory of probabilities is basically just common sense reduced to calculus; it makes one appreciate with exactness that which accurate minds feel with a sort of instinct, often without being able to account for it."”

Pierre-Simon Laplace

"On voit, par cet Essai, que la théorie des probabilités n'est, au fond, que le bon sens réduit au calcul; elle fait apprécier avec exactitude ce que les esprits justes sentent par une sorte d'instinct, sans qu'ils puissent souvent s'en rendre compte."
From the Introduction to Théorie Analytique des Probabilités http://visualiseur.bnf.fr/Visualiseur?Destination=Gallica&O=NUMM-88764, second and later editions; also published separately as Essai philosophique sur les Probabilités (1814). Œuvres complètes de Laplace, tome VII, p. cliii, Paris: Gauthier-Villars, 1878-1912.
Also reported as: "The theory of probabilities is at bottom nothing but common sense reduced to calculus; it enables us to appreciate with exactness that which accurate minds feel with a sort of instinct for which ofttimes they are unable to account."
Or as: "Probability theory is nothing but common sense reduced to calculation."

Feeling , Sense