Self-love is not opposed to the love of other people. You cannot really love yourself and do yourself a favor without doing other people a favor, and vice versa.
This is true joy of life-being used for a purpose that is recognized by yourself as a mighty one ... instead of being a feverish, selfish little clod of ailments and grievances, complaining that the world will not devote itself to making you happy.
There is certainly no greater happiness than to be able to look back on a life usefully and virtuously employed, to trace our own progress in existence by such tokens as excite neither shame nor sorrow.