John Leonard wrote:

    It occurred to me the other evening, that the universe is supposed to be
~14 billion years old. Life on Earth is supposed to be ~3.5 billion years
old. Human life is <1 million years.

    At one time, people thought that they, and the Earth, were at the center
of the universe. However that perception changed to one in which the Sun is
the center of the Universe. And from there, the Sun became the center of the
Solar System, which became another part of the Milky Way, which became
another part of the known Universe. Instead of being at the center of
everything, we were in the middle of nowhere and were simply average.

    Average is a working guideline which has been found useful. It is nothing more than that.

    A common conception of evolution put us at the head of the list of
species ('Created in the image of God'). As if the object of evolution is to
produce us and our kind. Now this is known to be false. We are just another
species competing for ground on this here green earth.

    It seems that one of the results of Scientific progress is to disabuse
us of an infantile concept of ourselves as being the center of everything
and replace it with another conception in which we are merely average.

    There is nothing infantile about it. It is also a good working observation once beyond hunter/gather but not for H/G cultures. Post H/G only got out of it by the accumulation of facts.

    If this interpretation is correct then given the age of the Universe and
the variation about an average (say, our Earth's age) that would be expected
(this is essentially a guess), what possibilities might exist regarding life
in our Universe? In other words if we were to assume that we are not unique
what might be the actual age of life? Is it reasonable to guess, merely on
the basis of our (supposed) averageness that it could be much greater than
our own?

    Time scales are almost immaterial to this dicussion. Create the "Twin Earth" on the other side of the sun (by magic) and make it identical but only twenty years ahead of us in technology. They would have visited by now. Next put them a hundred years ahead of us. You can see a trivial fraction of the age of the universe accomplishes miraculous differences.

    Do not bother working up a sweat over a billion years when a mere 100 is unimaginable.