French Astronomer and Mathematician
Pierre-Simon Laplace, Compte de Laplace, Marquis de Laplace
French Astronomer and Mathematician
At the bottom the theory of probabilities is only common sense expressed in numbers.
The ingenious method of expressing every possible number using a set of ten symbols (each symbol having a place value and an absolute value) emerged in India. The idea seems so simple nowadays that its significance and profound importance is no longer appreciated ... The importance of this invention is more readily appreciated when one considers that it was beyod the two greatest men of antiquity, Archimedes and Apollonius.
By shortening the labors doubled the life of the astronomer.
The last thing we expect of you, General, is a lesson in geometry!
How can this be! You made the system of the world, you explain the laws of all creation, but in all your book you speak not once of the existence of God!
The theory of probabilities is basically only common sense reduced to a calculus. It makes one estimate accurately what right-minded people feel by a sort of instinct, often without being able to give a reason for it.
How is it that, although you say so much about the Universe, you say nothing about its Creator?
Were she then to watch me live through it, she might smile condescendingly, as one who watches a marionette dance to the tugs of strings that it knows nothing about.
I have lived long enough to know what I did not at one time believe - that no society can be upheld in happiness and honor without the sentiment of religion.
What we know is not much. What we do not know is immense. [Allegedly last words]
I have wanted to establish that the phenomena of nature reduced in the final analysis to action-at-a-distance from molecule to molecule and that the consideration of these actions ought to serve as the basis of the mathematical theory of these phenomena.
Without any doubt, the regularity which astronomy shows us in the movements of the comets takes place in all phenomena. The trajectory of a simple molecule of air or vapor is regulated in a manner as certain as that of the planetary orbits; the only difference between them is that which is contributed by our ignorance. Probability is relative in part to this ignorance, and in part to our knowledge.
I see with much pleasure that you are working on a large work on the integral Calculus... The reconciliation of the methods which you are planning to make, serves to clarify them mutually, and what they have in common contains very often their true metaphysics; this is why that metaphysics is almost the last thing that one discovers. The spirit arrives at the results as if by instinct; it is only on reflecting upon the route that it and others have followed that it succeeds in generalizing the methods and in discovering its metaphysics.
You have written this huge book on the system of the world without once mentioning the author of the universe!
If man were restricted to collecting facts the sciences were only a sterile nomenclature and he would never have known the great laws of nature. It is in comparing the phenomena with each other, in seeking to grasp their relationships, that he is led to discover these laws.
If you can?t explain something simply, you don?t understand it well enough. [also attributed to Albert Einstein]
Indeed, Sire, Monsieur Lagrange has, with his usual sagacity, put his finger on the precise difficulty with the hypothesis: it explains everything, but predicts nothing.
Life?s most important questions are, for the most part, nothing but probability problems.
NAPOLEON: M. Laplace, they tell me you have written this large book [SystŠme du Monde] on the system of the universe, and have never even mentioned its Creator. LAPLACE: I have no need for this hypothesis.
One sees? 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.
Read Euler, read Euler, he is our master in everything.
Read Euler, read Euler, he is the master of us all.
All events, who by their smallness seem not consequences of natural laws, are in fact outcomes as necessary as celestial movements [...] but because of our ignorance of the immense majority of the data required and our inability to submit to computation most of the data we do know of? we attribute these phenomena to randomness... an expression of nothing more than our ignorance."
The curve described by a simple molecule of air or vapor is regulated in a manner just as certain as the planetary orbits; the only difference between them is that which comes from our ignorance.
We may regard the present state of the universe as the effect of its past and the cause of its future. An intellect which at a certain moment would know all forces that set nature in motion, and all positions of all items of which nature is composed, if this intellect were also vast enough to submit these data to analysis, it would embrace in a single formula the movements of the greatest bodies of the universe and those of the tiniest atom; for such an intellect nothing would be uncertain and the future just like the past would be present before its eyes.