You can't convince a believer of anything; for their belief is not based on evidence, it's based on a deep seated need to believe. - Carl Sagan

The nature of life on Earth and the search for life elsewhere are two sides of the same question — the search for who we are.

A faith-healer may or may not start out with fraud in mind. But to his amazement, his patients actually seem to be improving. Their emotions are genuine, their gratitude heart-felt. When the healer is criticized, such people rush to his defence. Several elderly attendees of the channelling at the Sydney Opera House were incensed after the Sixty Minutes expose: ‘Never mind what they say,’ they told Alvarez, ‘we believe in you`.
These successes may be enough to convince many charlatans, no matter how cynical they were at the beginning, that they actually have mystical powers. Maybe they’re not successful every time. The powers come and go, they tell themselves. They have to cover the down time. If they must cheat a little now and then, it serves a higher purpose, they tell themselves. Their spiel is consumer-tested. It works.

At any rate, both because of the clear trend in the recent history of biology and because there is not a shred of evidence to support it, I will not in these pages entertain any hypotheses on what used to be called the mind-body dualism, the idea that inhabiting the matter of the body is something made of quite different stuff, called mind.