“Shaw's plays are the price we pay for Shaw’s prefaces.”

Similar remarks are also attributed to Winston Churchill, Groucho Marx and to Mark Twain
Disputed

Source: Again the Magic

Source: Bernard Shaw in Twilight (1943), II
Context: Shaw's emotional development was one with his intellectual strength. His path led him into the thick of the scrimmage, where more spontaneous natures defend themselves with the usual weapons of malice, humility, bad temper or conceit. But Shaw used the death ray of imperturbability. His feelings were never hurt, his envy never aroused, his conceit was a transparent fiction, he never quarreled.

What The Chairman Told Tom, from Odes II:6 (1965)

J. B. Priestley, "The War - And After", in Horizon magazine (January 1940), reprinted in War Decade : An Anthology of the 1940s (1989) by Andrew Sinclair

Act III
1910s, The Doctor's Dilemma (1911)

Hello Out There (1941)

Source: Heart of Ice A Triple Threat Novel with April Henry (Thomas Nelson), p. 215

Source: The Origins of the Sexual Impulse (1963), p. 158
Context: Sadism is plainly connected with the need for self-assertion. At the same time it cannot be separated from the idea of defeat. A sadist is a man, who, in some sense, has his back to the wall. Nothing is further from sadism, for example, than the cheerful, optimistic mentality of a Shaw or Wells.