The instincts of action are the favourite haunts of happiness.  To move, to creep, to stand,  to walk,  to run, to climb, to swim, at last to fly: what strange delight there is in these natural expressions of our powers! To be made whole, one must stretch his legs and make friends with the sun.

Are you broken-hearted ? Go out for a long tramp alone, and the spirits of the sky and the earth will heal you.

— The Mansions of  Philosophy, Will Durant