There have been great advances in the human condition due to science: recollect the horrors of childbirth, surgical operations, even of having a tooth out, a hundred years ago. If the human race is not extinguished there may be cures of cancer, senility, and other evils, so that happiness may outweigh unhappiness in the case of more and more individuals. Perhaps our far superior descendants of a million years hence (if they exist) will be possessed of a felicity unimaginable to us.

J. J. C. Smart, Ethics, Persuasion, and Truth, London, 1984, p. 141