Henri Poincaré

The true scientist is a man who is always asking questions.

The most beautiful theories are those that are the simplest.

The true scientist is a man who is always seeking the truth.

The scientist is not a man who knows everything, but a man who knows how to learn from his mistakes.

The true scientist is a man who is always open to new ideas.

The only objective reality is the one that is common to several thinking beings and that can be communicated to them.

Thought is only a flash in the middle of a long night, but it is this flash which means everything.

What is it that gives to the creations of the mathematician a character of unity and makes us recognize in them the work of the same mind? It is the beauty of the relations which he perceives and which he expresses.

A reality completely independent of the mind that conceives it, sees it or feels it, is an impossibility.

The most fruitful comparisons are those which bring together facts that are very different, but which are united by some hidden analogy.

The mind can only understand what it can create.

The harmony of the world is revealed in mathematical laws, which are the only true reality.

It is often said that experiments should be made without a preconceived idea. That is impossible. Not only would it make every experiment fruitless, but even if we wished to do so, it could not be done.

The only reality we can know is the one that our senses and our intelligence allow us to construct.

The scientist must not be content with observing, he must also experiment.

The search for truth is more precious than its possession.

Mathematics, rightly viewed, possesses not only truth, but supreme beauty—a beauty cold and austere, like that of sculpture, without appeal to any part of our weaker nature, without the gorgeous trappings of painting or music, yet sublimely pure, and capable of a stern perfection such as only the greatest art can show.

The most important discoveries are those which introduce new methods.

The universe is not a machine, but a thought.

The true reality is not what we see, but what we think.