“Reason does not work automatically; thinking is not a mechanical process; the connections of logic are not made by instinct. The function of your stomach, lungs or heart is automatic; the function of your mind is not. In any hour and issue of your life, you are free to think or to evade that effort. But you are not free to escape from your nature, from the fact that reason is your means of survival—so that for you, who are a human being, the question ‘to be or not to be’ is the question ‘to think or not to think.’”

in Ayn Rand, Objectivism, Writers