"If a man cannot do brain work without stimulants of any kind, he had better turn to hand work it is an indication on Nature's part that she did not mean him to be a head worker."

"Nothing can be more incorrect than the assumption one sometimes meets with, that physics has one method, chemistry another, and biology a third."

"Science is organized common sense where many a beautiful theory was killed by an ugly fact."

"All truth, in the long run, is only common sense clarified."

"Science is nothing, but trained and organized common sense."

"There is no sea more dangerous than the ocean of practical politics none in which there is more need of good pilotage and of a single, unfaltering purpose when the waves rise high."

"The best men of the best epochs are simply those who make the fewest blunders and commit the fewest sins."

"Every great advance in natural knowledge has involved the absolute rejection of authority."

"The only medicine for suffering, crime, and all other woes of mankind, is wisdom. Teach a man to read and write, and you have put into his hands the great keys of the wisdom box. But it is quite another thing to open the box."

"I do not say think as I think, but think in my way. Fear no shadows, least of all in that great spectre of personal unhappiness which binds half the world to orthodoxy."

"It is not to be forgotten that what we call rational grounds for our beliefs are often extremely irrational attempts to justify our instincts."

"The struggle for existence holds as much in the intellectual as in the physical world. A theory is a species of thinking, and its right to exist is coextensive with its power of resisting extinction by its rivals."

"The scientific imagination always restrains itself within the limits of probability."

"My experience of the world is that things left to themselves don't get right."

"I believe that history might be, and ought to be, taught in a new fashion so as to make the meaning of it as a process of evolution intelligible to the young."

"Learn what is true in order to do what is right."

"The chess-board is the world, the pieces are the phenomena of the universe, the rules of the game are what we call the laws of Nature. The player on the other side is hidden from us."

"I am content with nothing, restless and ambitious... and I despise myself for the vanity, which formed half the stimulus to my exertions. Oh would that I were one of those plodding wise fools who having once set their hand to the plough go on nothing doubting."

"Freedom and order are not incompatible... truth is strength... free discussion is the very life of truth."

"Sit down before fact as a little child, be prepared to give up every conceived notion, follow humbly wherever and whatever abysses nature leads, or you will learn nothing."

"In scientific work, those who refuse to go beyond fact rarely get as far as fact."

"In science, as in art, and, as I believe, in every other sphere of human activity, there may be wisdom in a multitude of counsellors, but it is only in one or two of them."

"History warns us that it is the customary fate of new truths to begin as heresies and to end as superstitions."

"No slavery can be abolished without a double emancipation, and the master will benefit by freedom more than the freed-man."

"Science and literature are not two things, but two sides of one thing."

"Of moral purpose I see no trace in Nature. That is an article of exclusively human manufacture and very much to our credit."

"Ecclesiasticism in science is only unfaithfulness to truth."

"The world is neither wise nor just, but it makes up for all its folly and injustice by being damnably sentimental."

"The most considerable difference I note among men is not in their readiness to fall into error, but in their readiness to acknowledge these inevitable lapses."

"Science is simply common sense at its best, that is, rigidly accurate in observation, and merciless to fallacy in logic."

"No delusion is greater than the notion that method and industry can make up for lack of mother-wit, either in science or in practical life."

"It is the customary fate of new truths, to begin as heresies, and to end as superstitions."

"Economy does not lie in sparing money, but in spending it wisely."

"Science commits suicide when it adopts a creed."

"There is the greatest practical benefit in making a few failures early in life."

"Science reckons many prophets, but there is not even a promise of a Messiah."

"Books are the money of Literature, but only the counters of Science."

"The scientific spirit is of more value than its products, and irrationally held truths may be more harmful than reasoned errors."

"The Bible has been the Magna Carta of the poor and of the oppressed."

"The only freedom I care about is the freedom to do right; the freedom to do wrong I am ready to part with on the cheapest terms to anyone who will take it of me."

"Science has fulfilled her function when she has ascertained and enunciated truth."

"Patience and tenacity are worth more than twice their weight of cleverness."

"The great thing in the world is not so much to seek happiness as to earn peace and self-respect."

"Irrationally held truths may be more harmful than reasoned errors."

"The more rapidly truth is spread among mankind the better it will be for them. Only let us be sure that it is the truth."

"I protest that if some great Power would agree to make me always think what is true and do what is right, on condition of being turned into a sort of clock and would up every morning before I got out of bed, I should instantly close with the offer."

"It is one of the most saddening things in life that, try as we may, we can never be certain of making people happy, whereas we can almost always be certain of making them unhappy."

"Size is not grandeur, and territory does not make a nation."

"I take it that the good of mankind means the attainment, by every man, of all the happiness which he can enjoy without diminishing the happiness of his fellow men."

"Teach a child what is wise, that is morality. Teach him what is wise and beautiful, that is religion!"