Nearly every man who develops an idea works it up to the point where it looks impossible, and then he gets discouraged. That’s not the place to become discouraged.

Thomas Alva Edison

A person with a new idea is a crank until the idea succeeds.

Mark Twain

He was a wise man who originated the idea of God.

Euripides

The idea that to make a man work you’ve got to hold gold in front of his eyes is a growth, not an axiom. We’ve done that for so long that we’ve forgotten there’s any other way.

F. Scott Fitzgerald

My idea of an agreeable person is a person who agrees with me.

Benjamin Disraeli

So far as hypotheses are concerned, let no one expect anything certain from astronomy, which cannot furnish it, lest he accept as the truth ideas conceived for another purpose, and depart from this study a greater fool than when he entered it.

Nicolaus Copernicus

Mankind is not a circle with a single center but an ellipse with two focal points of which facts are one and ideas the other.

Victor Hugo

Fear is death, fear is sin, fear is hell, fear is unrighteousness, and fear is wrong life. All the negative thoughts and ideas that are in the world have proceeded from this evil spirit of fear.

Swami Vivekananda

All the forces in the world are not so powerful as an idea whose time has come.

Victor Hugo

The mind that opens to a new idea never returns to its original size.

Albert Einstein

One can resist the invasion of an army but one cannot resist the invasion of ideas.

Victor Hugo

Pure mathematics is in its way the poetry of logical ideas.

Albert Einstein

Our ideas must be as broad as Nature if they are to interpret Nature.

Arthur Conan Doyle

And suddenly, like light in darkness, the real truth broke in upon me; the simple fact of Man, which I had forgotten, which had lain deep buried and out of sight; the idea of community, of unity.

Ernst Toller

The difficulty lies not so much in developing new ideas as in escaping from old ones.

John Maynard Keynes

When I am traveling in a carriage, or walking after a good meal, or during the night when I cannot sleep; it is on such occasions that ideas flow best and most abundantly.

Wolfgang Amadeus Mozart

Ideas shape the course of history.

John Maynard Keynes

No other question has ever moved so profoundly the spirit of man; no other idea has so fruitfully stimulated his intellect; yet no other concept stands in greater need of clarification than that of the infinite.

David Hilbert

Ridicule is the only weapon which can be used against unintelligible propositions. Ideas must be distinct before reason can act upon them; and no man ever had a distinct idea of the trinity. It is the mere Abracadabra of the mountebanks calling themselves the priests of Jesus.

Thomas Jefferson

Some pacifists have carried the sound idea of the prime importance of security too far, to the point of declaring that any consideration of disarmament is superfluous and pointless as long as eternal peace has not been attained.

Ludwig Quidde

He can compress the most words into the smallest ideas of any man I ever met.

Abraham Lincoln

I have known a vast quantity of nonsense talked about bad men not looking you in the face. Don’t trust that conventional idea. Dishonesty will stare honesty out of countenance any day in the week, if there is anything to be got by it.

Charles Dickens

An idea, like a ghost, must be spoken to a little before it will explain itself.

Charles Dickens

Acting is nothing more or less than playing. The idea is to humanize life.

George Eliot

An invasion of armies can be resisted, but not an idea whose time has come.

Victor Hugo

Be less curious about people and more curious about ideas.

Marie Curie

I intend to leave after my death a large fund for the promotion of the peace idea, but I am skeptical as to its results.

Alfred Nobel