“He advocates suspension of judgment, with a proper suspicion of "Facts, the idlest of superstitions."Finally, although destructive to appearance, he is essentially reconstructive.”

The Kasîdah of Hâjî Abdû El-Yezdî (1870), Note I : Hâjî Abdû, The Man
Context: The Hâjî regrets the excessive importance attached to a possible future state: he looks upon this as a psychical stimulant, a day dream, whose revulsion and reaction disorder waking life. The condition may appear humble and prosaic to those exalted by the fumes of Fancy, by a spiritual dram-drinking which, like the physical, is the pursuit of an ideal happiness. But he is too wise to affirm or to deny the existence of another world. For life beyond the grave there is no consensus of mankind… Even the instinctive sense of our kind is here dumb. We may believe what we are taught: we can know nothing. He would, therefore, cultivate that receptive mood which, marching under the shadow of mighty events, leads to the highest of goals, — the development of Humanity. With him suspension of judgment is a system.

Hayek's Journey: The Mind of Friedrich Hayek (2003)

Pyrrho, 11.
The Lives and Opinions of Eminent Philosophers (c. 200 A.D.), Book 9: Uncategorized philosophers and Skeptics

Source: Why We Fail as Christians (1919), p. 72

Source: Uprooted

No. 117.
The Guardian (1713)

Article on Philosophy, Vol. 25, p. 667, as quoted in Main Currents of Western Thought : Readings in Western European Intellectual History from the Middle Ages to the Present (1978) by Franklin Le Van Baumer
Variant translation: Reason is to the philosopher what grace is to the Christian. Grace moves the Christian to act, reason moves the philosopher. Other men walk in darkness; the philosopher, who has the same passions, acts only after reflection; he walks through the night, but it is preceded by a torch. The philosopher forms his principles on an infinity of particular observations. … He does not confuse truth with plausibility; he takes for truth what is true, for forgery what is false, for doubtful what is doubtful, and probable what is probable. … The philosophical spirit is thus a spirit of observation and accuracy.
L'Encyclopédie (1751-1766)
Context: Reason is to the philosopher what grace is to the Christian.
Grace causes the Christian to act, reason the philosopher. Other men are carried away by their passions, their actions not being preceded by reflection: these are the men who walk in darkness. On the other hand, the philosopher, even in his passions, acts only after reflection; he walks in the dark, but by a torch.
The philosopher forms his principles from an infinity of particular observations. Most people adopt principles without thinking of the observations that have produced them, they believe the maxims exist, so to speak, by themselves. But the philosopher takes maxims from their source; he examines their origin; he knows their proper value, and he makes use of them only in so far as they suit him.
Truth is not for the philosopher a mistress who corrupts his imagination and whom he believes to be found everywhere; he contents himself with being able to unravel it where he can perceive it. He does not confound it with probability; he takes for true what is true, for false what is false, for doubtful what is doubtful, and probable what is only probable. He does more, and here you have a great perfection of the philosopher: when he has no reason by which to judge, he knows how to live in suspension of judgment...
The philosophical spirit is, then, a spirit of observation and exactness, which relates everything to true principles...

Il n'est et ne sera que l'avocat des pauvres.
1786
[in Gracchus Babeuf avec les Egaux, Jean-Marc Shiappa, Les éditions ouvrières, 1991, 73, 27082 2892-7]
On Maximilien de Robespierre

New York Times interview (1911)