If I am to constrain you by any law, it must be one by which I am also bound.

Enlightenment is man's emergence from his self-incurred immaturity.

Enthusiasm is always connected with the senses, whatever be the object that excites it. The true strength of virtue is serenity of mind, combined with a deliberate and steadfast determination to execute her laws. That is the healthful condition of the moral life; on the other hand, enthusiasm, even when excited by representations of goodness, is a brilliant but feverish glow which leaves only exhaustion and languor behind.

Democracy is necessarily despotism, as it establishes an executive power contrary to the general will; all being able to decide against one whose opinion may differ, the will of all is therefore not that of all: which is contradictory and opposite to liberty.

Even philosophers will praise war as ennobling mankind, forgetting the Greek who said: 'War is bad in that it begets more evil than it kills.'

All false art, all vain wisdom, lasts its time but finally destroys itself, and its highest culture is also the epoch of its decay.

So act that anything you do may become universal law.