The anthropic principle, arguably one of the most important intellectual topics of the 21st century, is explored in this intriguing article in Discover Magazine:
Physicists don’t like coincidences. They like even less the notion that life is somehow central to the universe, and yet recent discoveries are forcing them to confront that very idea.
Life, it seems, is not an incidental component of the universe, burped up out of a random chemical brew on a lonely planet to endure for a few fleeting ticks of the cosmic clock. In some strange sense, it appears that we are not adapted to the universe; the universe is adapted to us.
Call it a fluke, a mystery, a miracle. Or call it the biggest problem in physics. Short of invoking a benevolent creator, many physicists see only one possible explanation: Our universe may be but one of perhaps infinitely many universes in an inconceivably vast multiverse. Most of those universes are barren, but some, like ours, have conditions suitable for life.