“Genius is a curse. That's how I look at it. Some think that the brilliant comprehend the universe in a way the rest of us can't. They see the world how it truly is—and that reality is so horrible the lose their minds. Clarity leads to insanity.”

Variant: The area dividing the brain and the soul
Is affected in many ways by experience --
Some lose all mind and become soul:
insane.
Some lose all soul and become mind:
intellectual.
Some lose both and become:
accepted.
Source: You Get So Alone at Times That it Just Makes Sense

Variant: Some people never go crazy. What truly horrible lives they must lead.

Variant: Some lose all mind and become soul, insane. Some lose all soul and become mind, intellectual. Some lose both and become accepted.

De Abaitua interview (1998)
Context: Mind has come up with this brilliant way of looking at the world — science — but it can’t look at itself. Science has no place for the mind. The whole of our science is based upon empirical, repeatable experiments. Whereas thought is not in that category, you can’t take thought into a laboratory. The essential fact of our existence, perhaps the only fact of our existence – our own thought and perception is ruled off-side by the science it has invented. Science looks at the universe, doesn’t see itself there, doesn’t see mind there, so you have a world in which mind has no place. We are still no nearer to coming to terms with the actual dynamics of what consciousness is.

As quoted in "Master of the Secret World: John le Carré on Deception, Storytelling and American Hubris" by Andrew Ross, in Salon (21 October 1996); also in Conversations with John le Carré (2004) edited by Matthew Joseph Bruccoli and Judith Baughman, p. 141
Context: I use the furniture of espionage to amuse the reader, to make the reader listen to me, because most people like to read about intrigue and spies. I hope to provide a metaphor for the average reader's daily life. Most of us live in a slightly conspiratorial relationship with our employer and perhaps with our marriage. I think what gives my works whatever universality they have is that they use the metaphysical secret world to describe some realities of the overt world.

The Saviors of God (1923)
Context: With clarity and quiet, I look upon the world and say: All that I see, hear, taste, smell, and touch are the creations of my mind.
The sun comes up and the sun goes down in my skull. Out of one of my temples the sun rises, and into the other the sun sets.
The stars shine in my brain; ideas, men, animals browse in my temporal head; songs and weeping fill the twisted shells of my ears and storm the air for a moment.

No Reservations - Machu Picchu
Context: It seems that the more places I see and experience, the bigger I realize the world to be. The more I become aware of, the more I realize how relatively little I know of it, how many places I have still to go, how much more there is to learn. Maybe that's enlightenment enough - to know that there is no final resting place of the mind, no moment of smug clarity. Perhaps wisdom, at least for me, means realizing how small I am, and unwise, and how far I have yet to go.

Vol. I, p. 137
Letters to and from Dr. Samuel Johnson
Variant: The use of traveling is to regulate imagination by reality, and instead of thinking how things may be, to see them as they are.

Source: Your Forces and How to Use Them (1912), Chapter 7, p. 114