Imagine that a team of neuroscientists has just unveiled a technology that lets a person remove all trace of some terrible experience from his brain. Under what conditions, if any, would you use it? What might it be like to go through life knowing you'd once suffered an ordeal so dreadful that it demanded radical excision? How long could you endure this strange affirmative ignorance, this lost access to the unspeakable, without becoming neurotic, or even slightly mad? In the long run, might you not decide that such circumscribed amnesia was worse than whatever memory you'd felt compelled to erase?
Chapter 17 (p. 400) - The Philosopher's Apprentice (2008)