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No. 88: Jul-Aug 1993

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Humans have many ways to predict the future: animal entrails, Tarot cards, and the Copernican Principle. The Copernican Principle, in particular, leads to all sorts of profound prophecies.

The Copernican Primciple states that the earth does not occupy a special place in the cosmos. To this we add Darwinism, which asserts that, in the realm of biology, human origin is not special either; i.e., we enjoy no special place among life forms. Building upon these two general "beliefs," J.R. Gott, III, proceeds to estimate the longevities of various observables, such as the lifetime of a particular species. What follows is a long, highly technical computation of various probabilities, such as the evolution of intelligent life in the universe. All this (and there is a lot of it) leads to the following:

"Making only the assumption that you are a random intelligent observer, limits for the total longevity of our species of 0.2 million to 8 million years can be derived at the 95% confidence level. Further consideration indicates that we are unlikely to colonize the Galaxy, and that we are likely to have a higher population than the median for intelligent species."

Why won't we colonize the Galaxy? Not because we are not able to, Gott says, but because "living things do not usually live up to their maximum potential."

Also of interest here is Gott's assessment of SETI (our Search for Extraterrestrial Intelligence). Will our big radio telescopes pick up intelligent murmurings arriving from outer space? Gott's calculations are very pessimistic here:

"Thus, we do not expect to see a Dyson sphere civilization within our Galaxy, or a Karadashev type III civilization within the current observable horizon."

(Gott, J. Richard, III; "Implications of the Copernican Principle for Our Future Prospects." Nature, 363:315, 1993.)

*A line from Stephen Spender's poem: From All These Events, from the Slump, from the War, from the Boom.

Comment. But perhaps the Copernican Principle, Darwinism, or some other of Gott's assumptions are in error.

From Science Frontiers #88, JUL-AUG 1993. 1993-2000 William R. Corliss