The arbitrary rule of a just and enlightened prince is always bad. His virtues are the most dangerous and the surest form of seduction: they lull a people imperceptibly into the habit of loving, respecting, and serving his successor, whoever that successor may be, no matter how wicked or stupid.

All things must be examined, debated, investigated without exception and without regard for anyone's feelings... We must run roughshod over all these ancient puerilities, overturn the barriers that reason never erected, give back to the arts and sciences the liberty that is so precious to them.

What is this world? A complex whole, subject to endless revolutions. All these revolutions show a continual tendency to destruction; a swift succession of beings who follow one another, press forward, and vanish; a fleeting symmetry; the order of a moment. I reproached you just now with estimating the perfection of things by your own capacity; and I might accuse you here of measuring its duration by the length of your own days.

The first promise exchanged by two beings of flesh was at the foot of a rock that was crumbling into dust; they took as witness for their constancy a sky that is not the same for a single instant; everything changed in them and around them, and they believed their hearts free of vicissitudes. O children! always children!

The enjoyment of freedom which could be exercised without any motivation would be the real hallmark of a maniac.

There comes a moment during which almost every girl or boy falls into melancholy; they are tormented by a vague inquietude which rests on everything and finds nothing to calm it. They seek solitude; they weep; the silence to be found in cloister attracts them: the image of peace that seems to reign in religious houses seduces them. They mistake the first manifestations of a developing sexual nature for the voice of God calling them to Himself; and it is precisely when nature is inciting them that they embrace a fashion of life contrary to nature's wish.

Gentleness and peacefulness regulate our proceedings; theirs are dictated by fury. We employ reason, they accumulate faggots. They preach nothing but love, and breathe nothing but blood. Their words are humane, but their hearts are cruel.