“Fight any instinct to be humorless, for humorlessness is the worst of all absurdities.”

Source: Vestiges of the Natural History of Creation (1844), p. 320

Source: The Confessions of Aleister Crowley: An Autohagiography
Source: The Confessions of Aleister Crowley (1929), Ch. 57.
Context: Modern morality and manners suppress all natural instincts, keep people ignorant of the facts of nature and make them fighting drunk on bogey tales. … Knowing nothing and fearing everything, they rant and rave and riot like so many maniacs. The subject does not matter. Any idea which gives them an excuse of getting excited will serve. They look for a victim to chivy, and howl him down, and finally lynch him in a sheer storm of sexual frenzy which they honestly imagine to be moral indignation, patriotic passion or some equally avowable emotion. It may be an innocent Negro, a Jew like Leo Frank, a harmless half-witted German; a Christ-like idealist of the type of Debs, an enthusiastic reformer like Emma Goldman or even a doctor whose views displease the Medial Trust.

Quote of De Vlaminck; as cited in Les Fauves, The Museum of Modern Art; Simon & Schuster, New York, 1952; quoted in 'Becoming an Artist' on Widewalls https://www.widewalls.ch/artist/maurice-de-vlaminck/
Quotes undated

Je ne suis d'aucune faction, je les combattrai toutes.
Discours pour la défense de Robespierre http://www.royet.org/nea1789-1794/archives/discours/stjust_defense_robespierre_27_07_94.htm, speech to the National Convention (July 27, 1794).

Definitions and objects

Force of Circumstances Vol. III (1963) as translated by Richard Howard (1968) - Excerpt online http://www.marxists.org/reference/subject/ethics/de-beauvoir/1963/interview.htm
General sources
Context: It was said that I refused to grant any value to the maternal instinct and to love. This was not so. I simply asked that women should experience them truthfully and freely, whereas they often use them as excuses and take refuge in them, only to find themselves imprisoned in that refuge when those emotions have dried up in their hearts. I was accused of preaching sexual promiscuity; but at no point did I ever advise anyone to sleep with just anyone at just any time; my opinion on this subject is that all choices, agreements and refusals should be made independently of institutions, conventions and motives of self-aggrandizement; if the reasons for it are not of the same order as the act itself, then the only result can be lies, distortions and mutilations.

Source: Women Can't Hear What Men Don't Say (2000), p. 40.

"On Relativism" (1925)
Context: Socialism is good when it comes to wages, but it tells me nothing when it comes to other questions in life that are more private and painful, for which I must seek answers elsewhere. Relativism is not indifference; on the contrary, passionate indifference is necessary in order for you not to hear the voices that oppose your absolute decrees … Relativism is neither a method of fighting, nor a method of creating, for both of these are uncompromising and at times even ruthless; rather, it is a method of cognition. If one must fight or create, it is necessary that this be preceded by the broadest possible knowledge... One of the worst muddles of this age is its confusing of the ideas behind combative and cognitive activity. Cognition is not fighting, but once someone knows a lot, he will have much to fight for, so much that he will be called a relativist because of it.