The Great Filter

I often wonder about The Great Filter.

Conventional scientific wisdom holds that as there are close to 100 billion stars, about 500 billion planets and possibly 10 billion earth-like planets around those stars (all this just in the Milky Way), the chances of intelligent life are high.

We just haven't met any yet.

Why?

My favourite explanation is the one that might hold out the least hope for humanity - The Great Filter.

This theory suggests that there is an existential filter that all intelligent life must pass through in order to continue its existence. It is possible this filter is behind us, and human beings may be the only intelligent life to have ever made it through.

Or, and this is the more interesting and more plausible part of the theory, the filter is ahead of us. The reason we have not encountered peripatetic extraterrestrial beings is that when an intelligent species or civilisation reaches a certain level of technological advancement, it will invent the means of its own destruction. When it does so, it will destroy itself. And this happens before a civilisation figures out inter-galactic transport and communication.

Climate change, nuclear war, lethal pandemics, either naturally arising or through genetically engineered superbugs and biological warfare, or a destructive artificial general intelligence: there are a number of existential threats to human life we are already dealing with or are aware might lurk in our near future. Nick Bostrom feels that the destruction of intelligent life on a planet is most likely to come from an event caused by a technological discovery.

This would mean that we do all we do just for its own sake in the moment, and not to fulfil some planetary or spiritual destiny. There's a curious beauty in that.