Never continue in a job you don't enjoy. If you're happy in what you're doing you'll like yourself you'll have inner peace. And if you have that along with physical health you will have had more success than you could possibly have imagined.
Wrinkles should merely indicate where smiles have been.
Anyone who stops learning is old whether at twenty or eighty. Anyone who...
Age is an issue of mind over matter. If you don't mind it doesn't matter.