““Every creature has fear,” Jared said. “Even the non-conscious ones.”
“No,” Boutin said. “Every creature has a survival instinct. It looks like fear but it’s not the same thing. Fear isn’t the desire to avoid death or pain. Fear is rooted in the knowledge that what you recognize as yourself can cease to exist. Fear is existential.”
Source: The Ghost Brigades (2006), Chapter 13 (p. 286)
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John Scalzi 68
American science fiction writer 1969Related quotes

“For it is not death or pain that is to be feared, but the fear of pain or death.”
Book II, ch. 1 http://classics.mit.edu/Epictetus/discourses.2.two.html
Discourses
Variant: For death or pain is not formidable, but the fear of pain or death.

5th Public Talk, Amsterdam, The Netherlands (30 May 1967)
1960s

Variant: Expose yourself to your deepest fear; after that, fear has no power, and the fear of freedom shrinks and vanishes. You are free.

“Even death is not to be feared by one who has lived wisely.”
As quoted in Wisdom for the Soul: Five Millennia of Prescriptions for Spiritual Healing (2006) edited by Larry Chang, p. 193
This is actually a pithy modern-day 'summary' of the "Abhaya Sutta" (AN 4.184). It appears in "Buddha’s Little Instruction Book" by Jack Kornfield (p88).
Unclassified

“Do the thing you fear and the death of fear is certain.”