Sogyal Rinpoche, in the Tibetan Book of Living and Dying.

Looking in will require of us great subtlety and great courage—nothing less than a complete shift in our attitude to life and to the mind. We are so addicted to looking outside ourselves that we have lost access to our inner being almost completely. We are terrified to look inward, because our culture has given us no idea of what we will find. We may even think that if we do we will be in danger of madness. This is one of the last and most resourceful ploys of ego to prevent us discovering our real nature.
So we make our lives so hectic that we eliminate the slightest risk of looking into ourselves. Even the idea of meditation can scare people. When they hear the words “egoless” or “emptiness,” they think experiencing those states will be like being thrown out of the door of a spaceship to float forever in a dark, chilling void. Nothing could be further from the truth. But in a world dedicated to distraction, silence and stillness terrify us; we protect ourselves from them with noise and frantic busyness. Looking into the nature of our mind is the last thing we would dare to do.

Sometimes I think we don’t want to ask any real questions about who we are, for fear of discovering there is some other reality than this one. What would this discovery make of how we have lived? How would our friends and colleagues react to what we now know? What would we do with the new knowledge? With knowledge comes responsibility. Sometimes even when the cell door is flung open, the prisoner chooses not to escape.”