“To master this instrument the religious thinker must make a preliminary study of logic, just as the lawyer must study legal reasoning. This is no more heretical in the one case than in the other. And logic must be learned from the ancient masters, regardless of the fact that they were not Muslims.”

Last lectures (1966), p. 19

Source: The Confessions of Aleister Crowley (1929), Ch. 17.

Attributed in Princeton & Mathematics: A Notable Record, Chaplin, Virginia, Princeton Alumni Weekly, May 9, 1958 http://www.princeton.edu/~mudd/finding_aids/mathoral/pmcxpaw.htm,

Source: Realistic models in probability (1968), p. 1

1860s, Reply to an Emancipation Memorial (1862)
Context: The subject presented in the memorial is one upon which I have thought much for weeks past, and I may even say for months. I am approached with the most opposite opinions and advice, and that by religious men, who are equally certain that they represent the Divine will. I am sure that either the one or the other class is mistaken in that belief, and perhaps in some respects both. I hope it will not be irreverent for me to say that if it is probable that God would reveal his will to others, on a point so connected with my duty, it might be supposed he would reveal it directly to me; for, unless I am more deceived in myself than I often am, it is my earnest desire to know the will of Providence in this matter. And if I can learn what it is I will do it! These are not, however, the days of miracles, and I suppose it will be granted that I am not to expect a direct revelation. I must study the plain physical facts of the case, ascertain what is possible, and learn what appears to be wise and right.
The subject is difficult, and good men do not agree.

"Democracy: Its Presumptions and Realities" (1932); also in The Spirit of Liberty: Papers and Addresses (1952), p. 99 - 100.
Extra-judicial writings
Context: When I hear so much impatient and irritable complaint, so much readiness to replace what we have by guardians for us all, those supermen, evoked somewhere from the clouds, whom none have seen and none are ready to name, I lapse into a dream, as it were. I see children playing on the grass; their voices are shrill and discordant as children's are; they are restive and quarrelsome; they cannot agree to any common plan; their play annoys them; it goes poorly. And one says, let us make Jack the master; Jack knows all about it; Jack will tell us what each is to do and we shall all agree. But Jack is like all the rest; Helen is discontented with her part and Henry with his, and soon they fall again into their old state. No, the children must learn to play by themselves; there is no Jack the master. And in the end slowly and with infinite disappointment they do learn a little; they learn to forbear, to reckon with another, accept a little where they wanted much, to live and let live, to yield when they must yield; perhaps, we may hope, not to take all they can. But the condition is that they shall be willing at least to listen to one another, to get the habit of pooling their wishes. Somehow or other they must do this, if the play is to go on; maybe it will not, but there is no Jack, in or out of the box, who can come to straighten the game.

Everyman (2006)

"Hope and the Absurd in the work of Franz Kafka"
The Myth of Sisyphus (1942)