They Say Einstein Said

Two volumes of items collected and edited by Alice Calaprice, and published by the Princeton University Press, The Quotable Einstein, 1996 (ISBN 0691 02696-3) and The Expanded Quotable Einstein, 2000 (ISBN 0691 07021-0) contain items he said and others attributed to him, along with categories such as Probably Not By [indicated here by PNB with page citation].
Pages cited are either inside parentheses (year 1996 volume) or if alone from the year 2000 book. The first quote, date, and source are from the year 2000 book.

The creative principle [of science] resides in mathematics. June 10, 1933, Ideas and Opinions, 274.

Do not worry about your difficulties in mathematics; I can assure you that mine are still greater. (p. 177)

I never worry about the future. It comes soon enough. (p. 11), p. 15

Imagination is more important than knowledge. - Albert Einstein, p. 10

If we knew what it was we were doing, it would not be called research, would it? - Albert Einstein

Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. - Albert Einstein

The ideals which have lighted my way, and time after time have given me new courage to face life cheerfully, have been Kindness, Beauty, and Truth. - Albert Einstein

Not everything that counts can be counted , and not everything that can be counted counts. PNB, p. 316

It has become appallingly obvious that our technology has exceeded our humanity. - Albert Einstein

Reality is merely an illusion, albeit a very persistent one. - Albert Einstein

Everything should be made as simple as possible, but not simpler. Possibly by Einstein, p. 314

There are only two ways to live your life. One is as though nothing is a miracle. The other is as though everything is a miracle. PNB Einstein, p. 319

A person starts to live when he can live outside himself. - Albert Einstein

The secret to creativity is knowing how to hide your sources. - Albert Einstein

If you are out to describe the truth, leave elegance to the tailor. - Albert Einstein

Bear in mind that the wonderful things you learn in your schools are the work of many generations. All this is put in your hands as your inheritance in order that you may receive it, honor it, add to it, and one day faithfully hand it on to your children. - Albert Einstein

The right to search for truth also implies that one must not conceal any part of what one has recognized to be true. - Albert Einstein

Strive not to be a success, but rather to be of value. - Albert Einstein

The following statements by Albert Einstein were brought to my attention by Timothy Langston and are input from hardcopy he gave me. (Wherever "sic" appears I believe there could be either a punctuation or spelling error.)
Anyone who has never made a mistake has never tried anything new.

Before God we are equally wise - and equally foolish.

Few are those who see with their own eyes and feel with their own hearts.

Great spirits have always found violent opposition from mediocrities. The latter cannot understand it when a man does not thoughtfully submit to hereditary prejudices but honestly and courageously uses his own intelligence.

He who can no longer pause to wonder and stand rapt in awe, is as good as dead; his eyes are closed.

He who joyfully marches to music in rank and file has already earned my contempt. He has been given a large brain by mistake, since for him the spinal cord would fully suffice. This disgrace to civilization should be done away with at once. Heroism at command, senseless brutality, deplorable love-of-country stance, how violently I hate all this, how despicable and ignoble war is; I would rather be torn to shreds than to be a part of so base an action! It is my conviction that killing under the cloak of war is nothing but an act of murder.

How strange is the lot of us mortals! Each of us is here for a brief sojourn; for what purpose he knows not, though he senses it. But with deeper reflection one knows from daily life that one exists for other people.

I am absolutely convinced that no wealth in the world can help humanity forward even in the hands of the most devoted worker. The example of great and pure individuals is the only thing that can lead us to noble thoughts and deeds. Money only appeals to selfishness and irresistibly invites abuse. Can anyone imagine Moses, Jesus, or Gandhi armed with the money-bags of Carnegie. (sic)

I am enough of an artist to draw freely upon my imagination. Imagination is more important than knowledge. Knowledge is limited. Imagination encircles the world.

I think and think for months and years, ninety-nine times, the conclusion is false. The hundredth time I am right.

The important thing is not to stop questioning. Curiosity has its own reasons for existing. One cannot help but be in awe when he contemplates the mysteries of eternity, of life, of the marvelous structure of reality. It is enough if one tries to comprehend a little of this mystery every day. Never lose a holy curiosity.

In the middle of every difficulty lies opportunity. PNB, p. 321

The mere formulation of a problem is far more essential than its solution, which may be merely a matter of mathematical or experimental skills. To raise new questions, new possibilities, to regard old problems from a new angle requires creative imagination and marks real advances in science.

More and more I come to value charity and love of one's fellow being above everything else... All our lauded technological progress-our very civilization-is like the ax in the hand of the pathological criminal.

The most beautiful thing we can experience is the mysterious. It is the source of all true art and all science. He to whom this emotion is a stranger, who can no longer pause to wonder and stand rapt in awe, is as good as dead; his eyes are closed.

Our task must be to free ourselves from this prison by widening our circle of understanding and compassion to embrace all living creatures and the whole of nature and its beauty. Possibly By Einstein, p. 316

We cannot solve our problems with the same thinking we used when we created them.

Whoever undertakes to set himself up as a judge of Truth and Knowledge is shipwrecked by the laughter of the gods.

Note: There were two items from Timothy Langston's Homework Assignment in CS 190 that were already present in the list I'd posted to the web. Even without those items he found a third more quotations than I did.
12 3 2013 Version