“Why don't I kill myself? If I knew exactly what keeps me from doing so, I should have no more questions to ask myself since I should have answered them all.”

Girl, Interrupted (1994)
Context: It’s important to cultivate detachment. One way to do this is to practice imagining yourself dead, or in the process of dying. If there’s a window, you must imagine your body falling out the window. If there’s a knife, you must imagine the knife piercing your skin. If there’s a train coming, you must imagine your torso flattened under its wheels. These exercises are necessary to achieving the proper distance. The motive is paramount. Without a strong motive, you’re sunk. My motives were weak: an American-history paper I didn’t want to write and the question I’d asked months earlier, Why not kill myself? Dead, I wouldn’t have to write the paper. Nor would I have to keep debating the question.

There is no documented evidence that Camus ever wrote or said this, aside from Barry Schwartz's uncited mention in The Paradox of Choice. It is likely falsely attributed.
Disputed

Source: Jacques Lipchitz: The Artist at Work, 1966, p. 202

http://motls.blogspot.com/2017/03/czechs-vow-defiance-after-irrational-eu.html#more
The Reference Frame http://motls.blogspot.com/

Desde hace mil años me pregunto: ¿qué haré ahora? Y aún no necesito responderme.
Voces (1943)

Knowledge is Power
The Note-Books of Samuel Butler (1912), Part VII - On the Making of Music, Pictures, and Books