Knowing Yourself: The True in the False (1996)
Context: You think: you become that thought. And consciousness, or the state of pure awareness, is lost. The highest knowledge man can possess is that which is true in his own experience. If his experience is limited, so is his knowledge and he behaves accordingly.
“It is not good for a man to be too cognizant of his physical and spiritual mechanisms. Complete knowledge reveals limits to human possibilities, and the less a man is by nature limited in his purposes, the less he can tolerate limits.”
Fiasco (1986), Ch. 3, tr. Michael Kandel (1987)
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Stanisław Lem 74
Polish science fiction author 1921–2006Related quotes

“Man, limited by his nature, is infinite in his desires.”

As quoted in A Thousand Days: John F. Kennedy in the White House (1965) by Arthur M. Schlesinger, Jr., p. 291 books.google https://books.google.de/books?id=uFhNxX5lrNEC&pg=PA291&dq=stupidity

“Every man takes the limits of his own field of vision for the limits of the world.”
"Psychological Observations"
Parerga and Paralipomena (1851), Studies in Pessimism
Variant: Everyone takes the limits of his own vision for the limits of the world.
Source: Studies in Pessimism: The Essays

“Limited in his nature, infinite in his desires, man is a fallen god who remembers the heavens.”
Méditations Poétiques (1820), Sermon 2
“A man must know his limitations.”
Source: Drenai series, Legend, Pt 1: Against the Horde, Ch. 10

“When a man has put a limit on what he will do, he has put a limit on what he can do.”