Some people say that it would be arrogant to think that
humankind is the only intelligent life in the universe, but this
is is not a matter of emotion, rather one of sccience – and the
science is complicated. In a recent article, Astronomer Royal
Martin Rees wrote: “We know too little about how life began on
Earth to lay confident odds. It may have involved a fluke so
rare that it happened only once in the entire galaxy. On the
other hand, it may have been almost inevitable, given the right
environment. In the next two decades we can expect progress in
understanding the biochemistry of life’s origins: this is one of
the great unsolved problems – fascinating to the most Earth-
focused biologist, but also crucial in guiding astronomers on
how and where to search for alien life.” I am impressed by the
argument of Enrico Fermi which Rees summarises as follows: “The
great physicist Enrico Fermi famously argued that advanced life
must be rare. Many stars are a billion years older than our sun.
Life, were it common,