Elasticity-Toughness

To him whose elastic and vigorous thought keeps pace with the sun, the day is a perpetual morning. (Thoreau)

Life's a tough proposition, and the first hundred years are the hardest. (Mizner)

The time which we have at our disposal every day is elastic; the passions that we feel expand it, those that we inspire contract it; and habit fills up what remains. (Proust)