"Tennis is a sport where you have to be strong mentally and physically, but the mental part is even more important."
Words are wise men's counters, they do but reckon by them; but they are the money of fools.
You cannot hope to build a better world without improving the individuals. To that end, each of us must work for our own improvement and, at the same time, share a general responsibility for all humanity, our particular duty being to aid those to whom we think we can be most useful.