Though these young men unhappily fail tounderstand that the sacrifice of life is, in many cases, the easiest ofall sacrifices, and that to sacrifice, for instance, five or six years oftheir seething youth to hard and tedious study, if only to multiplytenfold their powers of serving the truth and the cause they have setbefore them as their goal--such a sacrifice is utterly beyond the strengthof many of them. 
Fyodor Dostoyevsky, The Brothers Karamazov
strength