La nécessité nous délivre de l'embarras du choix. - Luc de Clapiers, marquis de Vauvenargues

As soon as an opinion becomes common it is sufficient reason for men to abandon it and to uphold the opposite opinion until that in its turn grows old, and they require to distinguish themselves by other things. Thus if they attain their goal in some art or science, we must expect them soon to cast it aside to acquire some fresh fame, and this is partly the reason why the most splendid ages degenerate so quickly, and, scarcely emerged from barbarism, plunge into it again.

It is in our own mind and not in exterior objects that we perceive most things; fools know scarcely anything because they are empty, and their heart is narrow; but great souls find in themselves a number of exterior things; they have no need to read or travel or to listen or to work to discover the highest truths; they have only to delve into themselves and search, if we may say so, their own thoughts.

Some authors regard morality in the same light as we regard modern architecture. Convenience is the first thing to be looked for.