Cheerfulness is a matter of clarity and conviction. First
you have to be able to see beyond the present, to have such a vision that you
can sense a good future , not just for you but also for everything else; For
tell me now, how many times have you found rejoice in the misery of others?
You have to know in your bones that the whole movement of
the life is towards what is good and that all hills have valleys and all
seasons have summer. Then you have to live with that or else cheerfulness is just bravado
in the face of despair.