Henri Poincaré on Science

“To doubt everything or to believe everything are two equally convenient truths; both dispense with the necessity of reflection.”

“Science is built up with facts, as a house is with stones. But a collection of facts is no more a science than a heap of stones is a house.”

“There is no science apart from the general. It may even be said that the object of the exact sciences is to spare us these direct verifications.”

“It is only through science and art that civilization is of value. Some have wondered at the formula: science for its own sake; and yet it is as good as life for its own sake, if life is only misery; and even as happiness for its own sake, if we do not believe that all pleasures are of the same quality... Every act should have an aim. We must suffer, we must work, we must pay for our place at the game, but this is for seeing's sake; or at the very least that others may one day see.”

“Scientists believe there is a hierarchy of facts and that among them may be made a judicious choice. They are right, since otherwise there would be no science... One need only open the eyes to see that the conquests of industry which have enriched so many practical men would never have seen the light, if these practical men alone had existed and if they had not been preceded by unselfish devotees who died poor, who never thought of utility, and yet had a guide far other than caprice. As Mach says, these devotees have spared their successors the trouble of thinking.”

“Now what is science? ... It is before all a classification, a manner of bringing together facts which appearances separate, though they are bound together by some natural and hidden kinship. Science, in other words, is a system of relations. ... It is in relations alone that objectivity must be sought. ... It is relations alone which can be regarded as objective.''' External objects... are really objects and not fleeting and fugitive appearances, because they are not only groups of sensations, but groups cemented by a constant bond. It is this bond, and this bond alone, which is the object in itself, and this bond is a relation.”

“There might be a serious objection to classical studies. If it is to be desired that nine out of ten Frenchmen become good merchants and business men, is it not dangerous to disgust them beforehand with that which is to fill their lives? No doubt, it would not be impossible to refute such an objection; but that is no business mine. ... I seek what must be done to form men of science. And here all is clear. The man of science ought not tarry in the realization of practical aims; these, no doubt, he will obtain, but he must obtain them over and above. ...Science has wonderful applications; but the science which would have in view only applications would no longer be science—It would be only the kitchen. There is no science but disinterested science. ... The spirit which should animate the man science is that which breathed of old on Greece and brought there to birth poets and thinkers.''' There remains in our classical teaching I know not what of the Greek soul; I know not what that makes us look ever upward. And that is more precious for the making of a man of science than the reading of many volumes of geometry.”