If we wish to foresee the future of mathematics, our proper course is to study the history and present condition of the science. - Henri Poincaré

Je ne sais si je n’ai déjà dit quelque part que la Mathématique est l’art de donner le même nom à des choses différentes.

It follows from this that sight and touch could not have given us the notion of space without the aid of the 'muscular sense.

If... it be supposed that another way of measuring time is adopted... enunciation of the law would be... translated into another language... much less simple. So that the definition implicitly adopted by the astronomers may be summed up..: Time should be so defined that the equations of mechanics may be as simple as possible... [i.e.,] there is not one way of measuring time more true... only more convenient.