All heart surgeons are bastards, and Conway is no exception. - Michael Crichton

The fact that the biosphere responds unpredictably to our actions is not an argument for inaction. It is, however, a powerful argument for caution, and for adopting a tentative attitude toward all we believe, and all we do. Unfortunately, our species has demonstrated a striking lack of caution in the past. It is hard to imagine that we will behave differently in the future.

We think we know what we are doing. We have always thought so. We never seem to acknowledge that we have been wrong in the past, and so might be wrong in the future. Instead, each generation writes off earlier errors as the result of bad thinking by less able minds — and then confidently embarks on fresh errors of its own.

We are one of only three species on our planet that can claim to be self-aware, yet self-delusion may be a more significant characteristic of our kind.

There's one problem with all psychological knowledge - nobody can apply it to themselves. People can be incredibly astute about the shortcomings of their friends, spouses, children. But they have no insight into themselves at all. The same people who are coldly clear-eyed about the world around them have nothing but fantasies about themselves. Psychological knowledge doesn't work if you look in a mirror. This bizarre fact is, as far as I know, unexplained.

Most areas of intellectual life have discovered the virtues of speculation, and have embraced them wildly. In academia, speculation is usually dignified as theory.