“No, it is impossible; it is impossible to convey the life-sensation of any given epoch of one’s existence--that which makes its truth, its meaning--its subtle and penetrating essence. It is impossible. We live, as we dream--alone.”

The Genteel Tradition at Bay (1931)
Other works

Reading Lolita in Tehran (2003)

Hall and Fagen, "Definition of System," in Walter F. Buckley (1968) Modern Systems Research, p. 82

Part 3, Ch. 12, § 3.
The Origins of Totalitarianism (1951)
Context: The concentration camps, by making death itself anonymous (making it impossible to find out whether a prisoner is dead or alive), robbed death of its meaning as the end of a fulfilled life. In a sense they took away the individual’s own death, proving that henceforth nothing belonged to him and he belonged to no one. His death merely set a seal on the fact that he had never existed.

As quoted in Lindbergh (1998) by A. Scott Berg, p. 3

Source: 1980s, The Ecstasy of Communication (1987), p. 73

Source: Black and Blue

Source: The Limits of Evolution, and Other Essays, Illustrating the Metaphysical Theory of Personal Ideaalism (1905), Modern Science and Pantheism, p.79-80

Source: Journey to the End of the Night