“It is so easy to convince others; it is so difficult to convince oneself.”

"The Sublime and the Good", in the Chicago Review, Vol. 13 Issue 3 (Autumn 1959) p. 51.
Source: Existentialists and Mystics Writings on Philosophy and Literature

Source: Dictionary of Burning Words of Brilliant Writers (1895), P. 477.

Source: The Magician King

"The Lover and the Beloved", p. 1.
The Everything and the Nothing (1963)

The Principles of Success in Literature (1865)
Context: A man must be himself convinced if he is to convince others. The prophet must be his own disciple, or he will make none. Enthusiasm is contagious: belief creates belief. There is no influence issuing from unbelief or from languid acquiescence. This is peculiarly noticeable in Art, because Art depends on sympathy for its influence, and unless the artist has felt the emotions he depicts we remain unmoved: in proportion to the depth of his feeling is our sympathetic response; in proportion to the shallowness or falsehood of his presentation is our coldness or indifference.

Thoughts on Various Subjects from Miscellanies (1711-1726)

On Freedom (1958)
Context: The true Enlightenment thinker, the true rationalist, never wants to talk anyone into anything. No, he does not even want to convince; all the time he is aware that he may be wrong. Above all, he values the intellectual independence of others too highly to want to convince them in important matters. He would much rather invite contradiction, preferably in the form of rational and disciplined criticism. He seeks not to convince but to arouse — to challenge others to form free opinions.

Farewell, p. 453
1920s, An Autobiography (1927)