Health is the soul that animates all the enjoyments of life, which fade and are tasteless without it.

With the fearful strain that is on me night and day, if I did not laugh I should die.

The math is dead simple: it seems that the frequency of planets able to support life is roughly one percent. In other words, a billion or more such worlds exist in our galaxy alone. That's a lot of acreage, and it takes industrial-strength credulity to believe it's all bleakly barren.

Seek not, my soul, the life of the immortals; but enjoy to the full the resources that are within thy reach.

Any society that could come here could pick up the lights from New York. What should we do about that? Should we darken New York from now until the last human expires? Would we want to turn off all the radars at JFK airport?