Leonhard Euler

For the properties of numbers, which are so numerous and so wonderful, are discovered by the most simple means, namely by mere contemplation, but they are of such a nature that they cannot be understood by the human mind without great difficulty.

Commentarii Academiae Scientiarum Imperialis Petropolitanae

Although I am blind, I can still work.

Biographical accounts

The value of a problem is not so much in coming up with the answer as in the ideas and methods one develops in solving it.

Attributed

It is therefore not surprising that the properties of numbers, which are so numerous and so wonderful, are discovered by the most simple means, namely by mere contemplation.

Commentarii Academiae Scientiarum Imperialis Petropolitanae

I am not a mathematician, I am a calculator.

Attributed

The more I contemplate the works of God, the more I am astonished.

Letters to a German Princess

The study of mathematics is the study of the universe.

Attributed

I have often been asked how I have been able to make so many discoveries. The answer is simple: I have always been working.

Biographical accounts

Madam, I have come from a country where people are hanged for less.

Anecdote, likely apocryphal, regarding a conversation with Catherine the Great.

To the question of whether God exists, I answer: Sir, e^(iπ) + 1 = 0. Therefore God exists.

Anecdote, likely apocryphal, often attributed to a debate with Denis Diderot.

Although I am blind, I can still see the numbers.

Reported by his contemporaries after he lost his sight.

The more I study, the more I am convinced that the world is not as simple as it seems.

Attributed, but exact source is elusive.

My pen seems to flow with more ease than my tongue.

Attributed, reflecting his personality.

For the sake of brevity, I shall omit the proof.

Common phrase in his writings, sometimes used when the proof was indeed complex.

The value of a problem is not so much in coming up with the answer, but in the process of solving it.

Attributed, reflecting his approach to mathematics.

I have often found that a problem which I could not solve in the morning, I could solve in the evening.

Attributed, reflecting his work habits.

It is a truth universally acknowledged, that a single man in possession of a good fortune, must be in want of a wife.

While this is Jane Austen, it's a humorous misattribution often used to highlight the universality of certain 'truths' in a sardonic way, which Euler might appreciate in a mathematical context.

If you want to learn mathematics, you must do mathematics.

A practical and direct piece of advice.

I am not afraid of difficulties, for I know that they are only opportunities for growth.

Attributed, reflecting a positive outlook.

The art of asking questions is the source of all knowledge.

Attributed, highlighting the importance of inquiry.

Quotes by Leonhard Euler