“Whenever a man talks he lies, and so far as he talks to himself — that is to say, so far as he thinks, knowing that he thinks — he lies to himself.”

Source: The Rum Diary

Source: The Queen of Attolia

On Fairy-Stories (1939)
Context: I have claimed that Escape is one of the main functions of fairy-stories, and since I do not disapprove of them, it is plain that I do not accept the tone of scorn or pity with which 'Escape' is now so often used. Why should a man be scorned if, finding himself in prison, he tries to get out and go home? Or if he cannot do so, he thinks and talks about other topics than jailers and prison-walls? The world outside has not become less real because the prisoner cannot see it.

Ez ist ein armer trügesite,
der vriunden alsô liuget,
daz er sich selben triuget.
Source: Tristan, Line 12308

In Lugalbanda and the Anzud Bird, Ur III Period (21st century BCE). http://etcsl.orinst.ox.ac.uk/cgi-bin/etcsl.cgi?text=t.1.8.2.2#
Context: Lugalbanda lies idle in the mountains, in the faraway places; he has ventured into the Zabu mountains. No mother is with him to offer advice, no father is with him to talk to him. No one is with him whom he knows, whom he values, no confidant is there to talk to him. In his heart he speaks to himself: "I shall treat the bird as befits him, I shall treat Anzud as befits him. I shall greet his wife affectionately. I shall seat Anzud's wife and Anzud's child at a banquet. An will fetch Ninguena for me from her mountain home -- the expert woman who redounds to her mother's credit, the expert who redounds to her mother's credit. Her fermenting-vat is of green lapis lazuli, her beer cask is of refined silver and of gold. If she stands by the beer, there is joy, if she sits by the beer, there is gladness; as cupbearer she mixes the beer, never wearying as she walks back and forth, Ninkasi, the keg at her side, on her hips; may she make my beer-serving perfect. When the bird has drunk the beer and is happy, when Anzud has drunk the beer and is happy, he can help me find the place to which the troops of Unug are going, Anzud can put me on the track of my brothers."

Space (1912)
Context: Remember his mind and no other part of him lived in his new world. He said it gave him an odd sense of detachment to sit in a room among people, and to know that nothing there but himself had any relation at all to the infinite strange world of Space that flowed around them. He would listen, he said, to a great man talking, with one eye on the cat on the rug, thinking to himself how much more the cat knew than the man.

"On Invisibility" in Diary of an Unknown (1953)

Source: Aphorisms and Reflections (1901), p. 233