Regret, sure, but since we can't change the past that regret should motivate us to work harder to make the present and future better. We're a young species, an

Regret, sure, but since we can't change the past that regret should motivate us to work harder to make the present and future better. We're a young species, and part of growing up is looking back with chagrin at how foolish we seem in the light of our new growth and learning.