Henri Poincaré quotes

Henri Poincaré was a French mathematician, theoretical physicist, and philosopher of science. Considered one of the last universalists, his work laid the foundations for chaos theory and modern topology. He made significant contributions to mathematical physics, celestial mechanics, and the philosophy of mathematics. Here are 104 of his quotes:

The scientist does not study nature because it is useful; he studies it because he delights in it, and he delights in it because it is beautiful.

Henri Poincaré

Science is built up of facts, as a house is with stones. But a collection of facts is no more a science than a heap of stones is a house.

Henri Poincaré

To doubt everything or to believe everything are two equally convenient solutions; both dispense with the necessity of reflection.

Henri Poincaré

If nature were not beautiful, it would not be worth knowing, and if nature were not worth knowing, life would not be worth living.

Henri Poincaré

It is through science that we prove, but through intuition that we discover.

Henri Poincaré

Mathematical discoveries, small or great are never born of spontaneous generation.

Henri Poincaré

In the old days when people invented a new function they had something useful in mind.

Henri Poincaré

If we knew exactly the laws of nature and the situation of the universe at the initial moment, we could predict exactly the situation of the same universe at a succeeding moment.

Henri Poincaré

Need we add that mathematicians themselves are not infallible?

Henri Poincaré

Sociology is the science which has the most methods and the least results.

Henri Poincaré

It is by logic that we prove, but by intuition that we discover. To know how to criticize is good, to know how to create is better.

Henri Poincaré

Mathematicians are born, not made.

Henri Poincaré

It is far better to foresee even without certainty than not to foresee at all.

Henri Poincaré

Thought must never submit, neither to a dogma, nor to a party, nor to a passion, nor to an interest, nor to a preconceived idea, nor to whatever it may be, save to the facts themselves, because, for thought, submission would mean ceasing to be.

Henri Poincaré

The mind uses its faculty for creativity only when experience forces it to do so.

Henri Poincaré

To invent is to discern, to choose.

Henri Poincaré

Doubting everything and believing everything are two equally convenient solutions that guard us from having to think.

Henri Poincaré

One would have to have completely forgotten the history of science so as to not remember that the desire to know nature has had the most constant and the happiest influence on the development of mathematics.

Henri Poincaré

It is the harmony of the diverse parts, their symmetry, their happy balance; in a word it is all that introduces order, all that gives unity, that permits us to see clearly and to comprehend at once both the ensemble and the details.

Henri Poincaré

What is it indeed that gives us the feeling of elegance in a solution, in a demonstration?

Henri Poincaré

A sane mind should not be guilty of a logical fallacy, yet there are very fine minds incapable of following mathematical demonstrations.

Henri Poincaré

Thought is only a flash between two long nights, but this flash is everything.

Henri Poincaré