Donatien Alphonse François de Sade (2 June 1740 – 2 December 1814) better known as the Marquis de Sade, was a French writer of philosophy-laden and often violent pornography, as well as some strictly philosophical works. His is a philosophy of extreme licentiousness, unrestrained by ethics, religion or law, with the egotistical pursuit of personal pleasure being the highest principle. Sade was incarcerated in various prisons and in an insane asylum for about 32 years of his life. Much of his writing was done during his imprisonment. The term "sadism" is derived from his name.

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• The law which attempts a man's life [capital punishment] is impractical, unjust, inadmissible. It has never repressed crime—for a second crime is every day committed at the foot of the scaffold.
  • Philosophy in the Bedroom, 'One More Effort, Frenchmen, If You Would Become Republicans'. (1795)

• I am a libertine, but I am not a criminal nor a murderer, and since I am compelled to set my apology alongside my vindication, I shall therefore say that it might well be possible that those who condemn me as unjustly as I have been might themselves be unable to offset the infamies by good works as clearly established as those I can contrast to my errors. I am a libertine, but three families residing in your area have for five years lived off my charity, and I have saved them from the farthest depths of poverty. I am a libertine, but I have saved a deserter from death, a deserter abandoned by his entire regiment and by his colonel. I am a libertine, but at Evry, with your whole family looking on, I saved a child—at the risk of my life—who was on the verge of being crushed beneath the wheels of a runaway horse-drawn cart, by snatching the child from beneath it. I am a libertine, but I have never compromised my wife’s health. Nor have I been guilty of the other kinds of libertinage so often fatal to children’s fortunes: have I ruined them by gambling or by other expenses that might have deprived them of, or even by one day foreshortened, their inheritance? Have I managed my own fortune badly, as long as I have had a say in the matter? In a word, did I in my youth herald a heart capable of the atrocities of which I today stand accused?... How therefore do you presume that, from so innocent a childhood and youth, I have suddenly arrived at the ultimate of premeditated horror? No, you do not believe it. And yet you who today tyrannize me so cruelly, you do not believe it either: your vengeance has beguiled your mind, you have proceeded blindly to tyrannize, but your heart knows mine, it judges it more fairly, and it knows full well it is innocent."
  • L’Aigle, Mademoiselle… (in a letter to his wife, from the Bastille)

The 120 Days of Sodom (1784)

• Le duc imita bientôt avec Bande-au-ciel la petite infamie de son ancien ami et il paria, quoique le vit fût énorme, d'avaler trois bouteilles de vin de sens froid pendant qu'on l'enculerait.
  • Translation: The Duc soon imitated his old friend's little infamy and wagered that, enormous as Invictus' prick might be, he could calmly down three bottles of wine while lying embuggered upon it.
  • The First Day

• Nos quatre libertins, à moitié ivres, mais résolus pourtant d'observer leurs lois, se contentèrent de baisers, d'attouchements, mais que leur tête libertine sut assaisonner de tous les raffinements de la débauche et de la lubricité.
  • Translation: Our four libertines, half-drunk but none the less resolved to abide their laws, contended themselves with kisses, fingerings, but their libertine intelligence knew how to season these mild activities with all the refinements of debauch and lubricity.
  • The First Day

• Le duc, le vit en l'air, serrait Augustine de bien près; il braillait, il jurait, il déraisonnait, et la pauvre petite, toute tremblante, se reculait toujours, comme la colombe devant l'oiseau de proie qui la guette et qui est près d'en faire sa capture.
  • Translation: The Duc, pike aloft, closed in upon Augustine; he brayed, he swore, he waxed unreasonable, and the poor little thing, all atremble, retreated like a dove before the bird of prey ready to pounce upon it.
  • The Second Day

Justine or The Misfortunes of Virtue (1787)

• ...there is a sum of evil equal to the sum of good, the continuing equilibrium of the world requires that there be as many good people as wicked people...

• Why do you complain of your fate when you could so easily change it?

• Nothing we can do outrages Nature directly. Our acts of destruction give her new vigour and feed her energy, but none of our wreckings can weaken her power.

• I think that if there were a God, there would be less evil on this earth. I believe that if evil exists here below, then either it was willed by God or it was beyond His powers to prevent it. Now I cannot bring myself to fear a God who is either spiteful or weak. I defy Him without fear and care not a fig for his thunderbolts.

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• At all times, in every century, every age, there has been such a connection between despotism and religion that it is infinitely apparent and demonstrated a thousand times over, that in destroying one, the other must be undermined, for the simple reason that the first will always put the law into the service of the second.

• Chimerical and empty being, your name alone has caused more blood to flow on the face of the earth than any political war ever will. Return to the nothingness from which the mad hope and ridiculous fright of men dared call you forth to their misfortune. You only appeared as a torment for the human race. What crimes would have been spared the world, if they had choked the first imbecile who thought of speaking of you.
  • On religion

• Crime is the soul of lust. What would pleasure be if it were not accompanied by crime? It is not the object of debauchery that excites us, rather the idea of evil.

• Friends are like women: when put to the test, the goods often prove defective.

• Imperious, choleric, irascible, extreme in everything, with a dissolute imagination the like of which has never been seen, atheistic to the point of fanaticism, there you have me in a nutshell.... Kill me again or take me as I am, for I shall not change.
  • Last Will and Testament

• Let us give ourselves indiscriminately to everything our passions suggest, and we will always be happy...Conscience is not the voice of Nature but only the voice of prejudice.

• Lycurgus, Numa, Moses, Jesus Christ, Mohammed, all these great rogues, all these great thought-tyrants, knew how to associate the divinities they fabricated with their own boundless ambition.

• One must do violence to the object of one's desire; when it surrenders, the pleasure is greater.

• Sex is as important as eating or drinking and we ought to allow the one appetite to be satisfied with as little restraint or false modesty as the other.

• Sex without pain is like food without taste.

• Social order at the expense of liberty is hardly a bargain.

• To kill a man in a paroxysm of passion is understandable, but to have him killed by someone else after calm and serious meditation and on the pretext of duty honourably discharged is incomprehensible.