A sound mind in a sound body, is a short, but full description of a happy state in this World: he that has these two, has little more to wish for; and he that wants either of them, will be little the better for anything else.
To be content with life -- or to live merrily, rather --all that is required is that we bestow on all things only a fleeting, superficial glance; the more thoughtful we become the more earnest we grow.
There are two kinds of discontent in this world. The discontent that works, and the discontent that wrings its hands. The first gets what it wants. The second loses what it has. There's no cure for the first, but success and there's no cure at all for the second.