We went to a talk at the San Mateo County Astronomical Society by Lynn Rothschild, an astrobiologist at NASA Ames, last Friday evening. Yes, NASA does pay people to think about life in outer space and I can't think of a better use of taxpayer money. And for those of us looking for a Grand Unified Theory of science, religion, and humanities--which I'm not--astrobiology is a good entry point.
Rothschild studies "extremophiles," creatures that live in extreme conditions on Earth. These studies suggest life could exist on a place like Venus, with its stifling toxic clouds, or on Mars, where it gets damn cold. (Although Mars has other problems, notably "chaotic obliquity," meaning the tilt of its axis changes dramatically over relatively short time periods. It rocks. The Earth doesn't because of our Moon.) One thinks of the bacteria living in the "smokers" or thermal vents on the ocean floor, but it turns out there are lots of other examples of extremophiles, including penguins. And us. Because one of the questions Rothschild raised was how to define "extremophile"--especially if we take out the requirement to "love" the extreme and say it's OK to merely tolerate it. Some bacteria live in pools of acid only because they can't get out. They thrive in the relative comfort of the lab ("I didn't know it could be like this!"). Apparently some biologists consider it cheating to grow a layer of blubber or develop the ability to make and wear coats--so a kid ice skating couldn't be an extremophile--but that's an arguable line to draw.
What became clear for me at this talk was how deeply science is imbued with philosophy. The notion of questioning what an "extremophile" really is, and working from the understanding that the definition is questionable, opens huge investigative possibilities. Humanists are all about questioning definitions, and it's time we all starting seeing this method as productive rather than merely undermining.