Radi Khrapko wrote:


Life is common on the Earth only

You ought to say we have the only live planet in the neighborhood. If
there were a planet one million light years away just teeming with
intelligent (and non-intelligent) life, it would be of no consequence to
us.

There could be a thousand planets in the Milky Way with highly
intelligent life, but so far seperated as to make interaction a
practical impossibility.

Bob Kolker