Every definition implies an axiom, since it asserts the existence of the object defined. The definition then will not be justified, from the purely logical point of view, until we have proved that it involves no contradiction either in its terms or with the truths previously admitted.

By and large, mothers and housewives are the only workers who do not have regular time off. They are the great vacationless class.

A confession has to be part of your new life.

The only justification for our concepts and system of concepts is that they serve to represent the complex of our experiences; beyond this they have no legitimacy. I am convinced that the philosophers have had a harmful effect upon the progress of scientific thinking in removing certain fundamental concepts from the domain of empiricism, where they are under our control, to the intangible heights of the a priori. For even if it should appear that the universe of ideas cannot be deduced from experience by logical means, but is, in a sense, a creation of the human mind, without which no science is possible, nevertheless the universe of ideas is just as little independent of the nature of our experience as clothes are of the form of the human body. This is particularly true of our concepts of time and space, which physicists have been obliged by the facts to bring down from the Olympus of the a priori in order to adjust them and put them in a serviceable condition.

I do not know but it is too much to read one newspaper a week. I have tried it recently, and for so long it seems to me that I have not dwelt in my native region. The sun, the clouds, the snow, the trees say not so much to me. You cannot serve two masters. It requires more than a day's devotion to know and to possess the wealth of a day.

Providence has given the French nation precisely two instruments, two arms, so to speak, with which it stirs up the world - the French language and the spirit of proselytism that forms the essence of the nation's character.

How is it possible that the poorer classes can remain healthy and have a reasonable expectation of life under such conditions? What can one expect but that they should suffer from continual outbreaks of epidemics and an excessively low expectation of life? The physical condition of the workers shows a progressive deterioration.

It is not titles that make men illustrious, but men who make titles illustrious.

One is rarely an impulsive innovator after the age of sixty, but one can still be a very fine orderly and inventive thinker. One rarely procreates children at that age, but one is all the more skilled at educating those who have already been procreated, and education is procreation of another kind.

May we not return to those scoundrels of old, the illustrious founders of superstition and fanaticism, who first took the knife from the altar to make victims of those who refused to be their disciples?

To be or not to be is not the question where transcendence is concerned. The statement of being's other, of the otherwise than being, claims to state a difference over and beyond that which separates being from nothingness - the very difference of the beyond, the difference of transcendence.

I am as firmly convinced that religions do harm as I am that they are untrue.

Not much younger than these (sc. Hermotimus of Colophon and Philippus of Mende) is Euclid, who put together the Elements, collecting many of Eudoxus' theorems, perfecting many of Theaetetus', and also bringing to irrefragable demonstration the things which were only somewhat loosely proved by his predecessors. This man lived in the time of the first Ptolemy. For Archimedes, who came immediately after the first (Ptolemy), makes mention of Euclid: and, further, they say that Ptolemy once asked him if there was in geometry any shorter way than that of the elements, and he answered that there was no royal road to geometry. He is then younger than pupils of Plato but older than Eratosthenes and Archimedes; for the latter were contemporary with one another, as Eratosthenes somewhere says.

I shall keep it [the manuscript] by me until the end of May for purposes of revision, and of adding malicious foot-notes.

It is the love of the people; it is their attachment to their government, from the sense of the deep stake they have in such a glorious institution, which gives you both your army and your navy, and infuses into both that liberal obedience, without which your army would be a base rabble, and your navy nothing but rotten timber.

I am not an Atheist. I do not know if I can define myself as a Pantheist. The problem involved is too vast for our limited minds. May I not reply with a parable? The human mind, no matter how highly trained, cannot grasp the universe. We are in the position of a little child, entering a huge library whose walls are covered to the ceiling with books in many different tongues. The child knows that someone must have written those books. It does not know who or how. It does not understand the languages in which they are written. The child notes a definite plan in the arrangement of the books, a mysterious order, which it does not comprehend, but only dimly suspects. That, it seems to me, is the attitude of the human mind, even the greatest and most cultured, toward God. We see a universe marvelously arranged, obeying certain laws, but we understand the laws only dimly. Our limited minds cannot grasp the mysterious force that sways the constellations. I am fascinated by Spinoza's Pantheism. I admire even more his contributions to modern thought. Spinoza is the greatest of modern philosophers because he is the first philosopher who deals with the soul and the body as one, not as two separate things.

Someone has said that it requires less mental effort to condemn than to think. The widespread mental indolence, so prevalent in society, proves this to be only too true. Rather than to go to the bottom of any given idea, to examine into its origin and meaning, most people will either condemn it altogether, or rely on some superficial or prejudicial definition of non-essentials.

Ironic philosophies produce passionate works. Any thought that abandons unity glorifies diversity! And diversity is the home of art. The only thought to liberate the mind is that which leaves it alone, certain of its limits and of its impending end. No doctrine tempts it. It awaits the ripening of the work and of life.

We think it also necessary to express our astonishment that a government, desirous of being called free, should prefer connection with the most despotic and arbitrary powers in Europe.

The establishment of any new manufacture, of any new branch of commerce, or any new practice in agriculture, is always a speculation, from which the projector promises himself extraordinary profits. These profits sometimes are very great, and sometimes, more frequently, perhaps, they are quite otherwise; but in general they bear no regular proportion to those of other older trades in the neighbourhood. If the project succeeds, they are commonly at first very high. When the trade or practice becomes thoroughly established and well known, the competition reduces them to the level of other trades.

Heroism feels and never reasons and therefore is always right.

For successful education there must always be a certain freshness in the knowledge dealt with. It must be either new in itself or invested with some novelty of application to the new world of new times. Knowledge does not keep any better than fish. You may be dealing with knowledge of the old species, with some old truth; but somehow it must come to the students, as it were, just drawn out of the sea and with the freshness of its immediate importance.

Every man has some reminiscences which he would not tell to everyone, but only to his friends. He has others which he would not reveal even to his friends, but only to himself, and that in secret. But finally there are still others which a man is even afraid to tell himself, and every decent man has a considerable number of such things stored away. That is, one can even say that the more decent he is, the greater the number of such things in his mind.

Solitude, the safeguard of mediocrity, is to genius the stern friend.

I regard Peter as one of the great moralists, because I suspect that more than anyone he has helped to change the attitudes of very many people to the sufferings of animals. Peter is a utilitarian in normative ethics, and a humane attitude to animals is a natural corollary of utilitarianism. Utilitarian concern for animals goes back to Bentham, who, presumably alluding to the Kantians, said that the question was not whether animals can reason, but whether they can suffer.

A clash of doctrines is not a disaster - it is an opportunity.

Mathematics have a triple aim. They must furnish an instrument for the study of nature. But that is not all: they have a philosophic aim and, I dare maintain, an esthetic aim. They must aid the philosopher to fathom the notions of number, of space, of time. And above all, their adepts find therein delights analogous to those given by painting and music. They admire the delicate harmony of numbers and forms; they marvel when a new discovery opens to them an unexpected perspective; and has not the joy they thus feel the esthetic character, even though the senses take no part therein? Only a privileged few are called to enjoy it fully, it is true, but is not this the case for all the noblest arts?This is why I do not hesitate to say that mathematics deserve to be cultivated for their own sake, and the theories inapplicable to physics as well as the others. Even if the physical aim and the esthetic aim were not united, we ought not to sacrifice either.

There is no more light in a genius than in any other honest man-but he has a particular kind of lens to concentrate this light into a burning point.

Such night in England ne'er had been, nor ne'er again shall be.

Theory is taught so as to make the student believe that he or she can become a Marxist, a feminist, an Afrocentrist, or a deconstructionist with about the same effort and commitment required in choosing items from a menu.

No longer able to believe in the Church religion, whose falsehood they had detected, and incapable of accepting true Christian teaching, which denounced their whole manner of life, these rich and powerful people, stranded without any religious conception of life, involuntarily returned to that pagan view of things which places life's meaning in personal enjoyment. And then among the upper classes what is called the "Renaissance of science and art" took place, which was really not only a denial of every religion, but also an assertion that religion was unnecessary.

Is it just I who cannot found a school, or can a philosopher never do so?

The importation of gold and silver is not the principal, much less the sole benefit which a nation derives from its foreign trade.

Fate and temperament are the names of a concept.

If you get the message, hang up the phone. For psychedelic drugs are simply instruments, like microscopes, telescopes, and telephones. The biologist does not sit with eye permanently glued to the microscope, he goes away and works on what he has seen.

There will be no mass-based feminist movement as long as feminist ideas are understood only by a well-educated few.

Where we find a difficulty we may always expect that a discovery awaits us. Where there is cover we hope for game.

Men are most apt to believe what they least understand.

Write as if thou wert alone in the universe and hadst nothing to fear from the jealousies and prejudices of the people. Otherwise thou wilt miss thy purpose.

All human activities are equivalent ... and ... all are on principle doomed to failure.

Somebody ought to make a historical study of the relations between theology and corporal punishment in childhood. I have a theory that, wherever little boys and girls are systematically flagellated, the victims grow up to think of God as - 'Wholly Other'... A people's theology reflects the state of its children's bottoms. Look at the Hebrews - enthusiastic child-beaters. And so were all good Christians in the Age of Faith. Hence Jehovah, hence Original Sin and the infinitely offended Father of Roman and Protestant orthodoxy. Whereas among Buddhists and Hindus education has always been nonviolent. No laceration of little buttocks - therefore Tat tvam asi, thou art That, mind from Mind is not divided.... Major premise: God is Wholly Other. Minor premise: man is totally depraved. Conclusion: Do to your children's bottoms what was done to yours, what your Heavenly Father has been doing to the collective bottom of humanity ever since the Fall: whip, whip, whip!

The supporters of the Development Hypothesis... can show that any existing species-animal or vegetable-when placed under conditions different from its previous ones, immediately begins to undergo certain changes fitting it for the new conditions. They can show that in successive generations these changes continue; until, ultimately, the new conditions become the natural ones. They can show that in cultivated plants, in domesticated animals, and in the several races of men, such alterations have taken place. They can show that the degrees of difference so produced are often, as in dogs, greater than those on which distinctions of species are in other cases founded.

The annual produce of the land and labour of any nation can be increased in its value by no other means, but by increasing either the number of its productive labourers, or the productive powers of those labourers who had before been employed.