All men's miseries derive from not being able to sit in a quiet room alone.
I think that age as a number is not nearly as important as health. You can be in poor health and be pretty miserable at 40 or 50. If you're in good health you can enjoy things into your 80s.
Nearly all the powerful people of this age are unbelievers the best of them in doubt and misery the most in plodding hesitation doing as well as they can what practical work lies at hand.
Life an age to the miserable and a moment to the happy.
It is with an old love as it is with old age a man lives to all the miseries but is dead to all the pleasures.
He who has not the spirit of this age has all the misery of it.