"Since humans are the first on this planet to acquire an
awareness of its setting in time and space, we bear the burden
of searching for cosmic kinships.
"If we are alone, the burden is especially onerous; for upon
us falls the responsibility of sustaining and expanding the
only oasis -- the extinction of which would make the solar
system a ghost town whose funereal presence would haunt
eternity with a reminder of what might have been.
"If, instead, we are a part of a much larger cosmic community,
our participation in its furtherance cannot be postponed indefinitely."
- George A. Seielstad, Chapter 6: "Other Worlds",
page 102, from Cosmic Ecology: The View from the Outside In,
University of California Press, Berkeley, 1983