There is no more lively sensation than that of pain; its impressions are certain and dependable, they never deceive as may those of the pleasure women perpetually feign and almost never experience.

Happiness is an abstraction, it is a product of the imagination, it is a way of being moved, which depends entirely on our way of seeing and feeling.

Humane sentiments are baseless, mad, and improper; they are incredibly feeble; never do they withstand the gainsaying passions, never do they resist bare necessity.

Certain souls seem hard because they are capable of strong feelings, and they sometimes go to rather extreme lengths; their apparent unconcern and cruelty are but ways, known only to themselves, of feeling more strongly than others.

Every principle is a judgment, every judgment the outcome of experience, and experience is only acquired by the exercise of the senses; whence it follows that religious principles bear upon nothing whatever and are not in the slightest innate. Ignorance and fear, you will repeat to them, ignorance and fear - those are the twin bases of every religion.

We monsters are necessary to nature also.

The mirror sees the man as beautiful, the mirror loves the man; another mirror sees the man as frightful and hates him; and it is always the same being who produces the impressions.