Deep Time

Release of the first images from the space telescope at L5 reminds me of a topic I've been meaning to remark upon.

I just read Annals of the Former World, by John McPhee. It's at least partially boring -- the frame is extensive touring of the United States with geologists, learning about the geological history of the North American continent -- although he doesn't really get to Canada or Mexico. The specific details pile up to form a mind numbing mountain, although he does manage to work in some interesting human stories along the way. But the main takeaway is the utter insignificance of these human stories, against the unimaginably vast backdrop of time. 

To borrow now from Carl Sagan's Dragons of Eden (about which I recently expressed some reservations), if we mapped the history of the universe onto a single calendar year, and set the origin at 1 minute after midnight on January 1, the earth would have formed on September 14. The oldest known rocks, and hence the beginning of John McPhee's story, formed on October 2 -- whatever was there before has disappeared, subducted into the mantle or overridden and buried so deep we cannot find it. The first eukaryotic cells appeared on November 15. The asteroid impact that wiped out the dinosaurs occurred on December 28. Our ancestor Homo erectus appeared at about 11:00 pm on December 31, one hour from midnight. and neolithic civilization -- the dawn of agriculture -- occurred at 11:59:35. All of human history -- that is, since the invention of writing -- has therefore happened in the last 25 seconds. And the scientific revolution has occurred in the final second, with the United States founded perhaps half a second ago.

People simply cannot comprehend a 4 1/2 billion year old earth, let alone a universe nearly 14 billion years old. And this makes it difficult for them to accept all of science. Evolution, the continents drifting around, crashing into each other and breaking apart, the origin and history of the universe -- all of these are essential to scientific understanding. You can't reject or ignore any of it and still have a coherent understanding of the rest. Perhaps even more difficult for many people is the implication that we just don't matter, in time and space we are nothing. Now, that isn't true from our own point of view -- we matter to ourselves and to each other. But that's the only way we matter. That is the humanist conclusion. It doesn't seem to work for some people, but it has the great virtue of being the truth.