An excerpt from the book, Man’s Search for Meaning by Viktor Frankl (1905-1997),
We who lived in concentration camps can remember the men who walked through the huts comforting others, giving away their last piece of bread. They may have been few in number, but they offer sufficient proof that everything can be taken from a man but one thing: the last of the human freedoms—to choose one’s attitude in any given set of circumstances, to choose one’s own way. And there were always choices to make. Every day, every hour, offered the opportunity to make a decision, a decision which determined whether you would or would not submit to those powers which threatened to rob you of your very self, your inner freedom; which determined whether or not you would become the plaything of circumstance, renouncing freedom and dignity to become moulded into the form of the typical inmate.
… in the final analysis it becomes clear that the sort of person the prisoner became was the result of an inner decision, and not the result of camp influences alone. Fundamentally, therefore, any man can, even under such circumstances, decide what shall become of him—mentally and spiritually. He may retain his human dignity even in a concentration camp. Dostoevsky said once, “There is only one thing that I dread: not to be worthy of my sufferings.” … It can be said that they were worthy of their sufferings; the way they bore their suffering was a genuine inner achievement. It is this spiritual freedom— which cannot be taken away—that makes life meaningful and purposeful.