Pierre-Simon Laplace

The ignorance in which we are of the true values of the observed quantities obliges us to employ procedures which show them with the greatest possible precision.

The entire method of probabilities is derived from a single principle: the probability of an event is the ratio of the number of cases favorable to it, to the total number of possible cases, when nothing leads us to believe that one of these cases should occur rather than the others.

The universe, if we consider it in its entirety, is governed by destiny; but in its details it is subject to chance.

The calculus of probabilities, when confined within just limits, ought to interest, in an equal degree, the mathematician, the experimentalist, and the statesman.

The phenomena of society depend upon so many variable elements, that it is impossible to foresee their course with certainty.

The laws of nature are so constant, that we cannot suppose them changed even in the most distant parts of the universe.

The history of science is the real history of mankind.

The human mind offers, in the perfection which it has been able to give to astronomy, a feeble idea of the intelligence which presides over the universe.

The knowledge which we have acquired of the laws of nature is the most solid basis of morality.

The true system of the world has been recognized, developed, and perfected only within the last century.

The application of analysis to the theory of probabilities is one of the most remarkable facts of modern mathematics.

The more a phenomenon is complicated, the more the causes which influence it are multiplied, and the more it is necessary to have recourse to the theory of probabilities.

The future, like the past, would be present before its eyes.

The regularity of the astronomical phenomena, the precision with which they return at the predicted times, is for us a proof that the celestial bodies are not moved by chance.

The calculus of probabilities is the most solid foundation of the sciences which depend upon observation.

The errors of observations are subject to a law which analysis makes known, and which one can regard as one of the most happy applications of the calculus of probabilities.

The universe is a grand book written in the language of mathematics.

The small inequalities which we observe in the movements of the planets are due to their mutual action, and they serve to determine their masses.

The analytical equations which express the laws of nature admit of singular solutions, which seem to be exceptions to these laws.

The progress of the calculus of probabilities has been very rapid since the time of Pascal and Fermat, who can be considered its inventors.