Rudyard Kipling

If you can dream and not make dreams your master;
If you can think and not make thoughts your aim;
If you can meet with triumph and disaster;
And treat those two imposters just the same,

If you can force your heart, and nerve, and sinew
To serve your turn long after they are gone;
And so hold on when there is nothing in you
Except the will which says to them, “Hold on,”

If you can fill the unforgiving minute
With sixty seconds’ worth of distance run,
Yours is the earth and everything that’s in it,
And, what is more, you’ll be a man, my son.