A Populated Galaxy?

Copied from Poul Anderson Appreciation, 15 Nov 2013.

I smell a very large rat here, folks. Please let me explain. But it will take a while.

The blurb on Poul Anderson's Is There Life On Other Worlds? (New York, 1963) says that Anderson:

"...ventures the startling conclusion that intelligent life is widespread throughout the cosmos." (back cover)

I am still reading the book but its argument is definitely pointing in that direction. Was such a conclusion really startling? In any case, one reservation here is that the book is now fifty years old. It is always necessary to check current scientific thinking on such issues. I will return to this point.

Meanwhile, however, for what it is worth, did the book when it was published provide a theoretical underpinning for the many sf works by Anderson and others who populated the galaxy with more or less humanoid sophonts? The matter is not quite that straightforward. There are two parallel traditions: literary and scientific. Hard sf is one literary tradition that does try to keep abreast of current science although the latter sometimes dates quickly.

Brian Aldiss points out somewhere that the earliest pre-literary and literary traditions populated Earth with many non-human intelligences that most of us now think do not exist. Next, fiction populated the Solar System with Wellsian Selenites or ERBian Moonmen, Martians, Venerians, Jovians etc. We now think that such beings do not exist. Literature may lag behind science. Thus, the early Asimov wrote about Martians and Venerians although he knew by then that they did not exist. CS Lewis wrote about Martian "canals" because they were part of the mythology, not because he still thought that they existed.

Aldiss thought that the populated galaxy was as mythical as the supernaturally populated Earth and the naturally populated Solar System. Of course, whether there really is any intelligent life elsewhere in the galaxy remains a scientific question but I think that we can be certain that, if there are any extra-Solar intelligences, then they are completely unlike any that have been imagined.

Back to the rat: in Anderson's much later future histories, Harvest Of Stars and Genesis, life is rare and extra-Solar intelligence is not encountered. Was Anderson merely trying out alternative sf premises or was he, as I strongly suspect, acknowledging more recent scientific thinking as to the likelihood or otherwise of life on other worlds?