No serious student of human behavior denies the potent influence of evolved biology upon our cultural lives. Our struggle is to figure out how biolog… - Stephen Jay Gould

The skein of human continuity must often become this tenuous across the centuries (hanging by a thread, in the old cliché), but the circle remains unbroken if I can touch the ink of Lavoisier's own name, written by his own hand. A candle of light, nurtured by the oxygen of his greatest discovery, never burns out if we cherish the intellectual heritage of such unfractured filiation across the ages. We may also wish to contemplate the genuine physical thread of nucleic acid that ties each of us to the common bacterial ancestor of all living creatures, born on Lavoisier's ancienne terre more than 3.5 billion years ago—and never since disrupted, not for one moment, not for one generation. Such a legacy must be worth preserving from all the guillotines of our folly.

I would rather label the whole enterprise of setting a biological value upon groups for what it is: irrelevant, intellectually unsound, and highly injurious.

Our planet is not fragile at its own timescale and we, pitiful latecomers in the last microsecond of our planetary year, are stewards of nothing in the long run.