True forest stewardship means leaving some trees - and some profits - for those who come after us.
The true power of mathematics is not in its complexity, but in its simplicity and elegance.
Our heroes are human heroes. That's a very new situation. Most other societies have had, right at their center, the worship of something transcendent: a god, a spirit, a natural force, the universe, whatever it is -- something else that is being worshiped. We've slightly lost the habit of doing that, which is, I think, why we're particularly drawn to nature.
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.