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Comment by Symmetry | Hacker News Reader

That's pretty comforting. As the solar system we live in seems more unusual it seems more credible that planets with advanced life might be rare. In which case the emptiness of the galaxy seems more explicable.

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Putting the Great Filter not merely behind us, but way behind us, would be a pretty cool scientific result.

There may be more than one Great Filter. We could have passed one of them, but we might not survive the next one.

The entire point of a "Great Filter" is that there is one that wipes out the majority of species that make it that far. If there are multiple then they're just likely cataclysmic events.

No, the Great Filter is more general than self-destruction. Some examples I've seen of possible Great Filters we've already passed include:

* The formation of any life at all

* The jump from single-celled life to multi-cellular organisms

* The ability to create/use/pass on knowledge of tools

The point of the Great Filter argument is that something seems to be preventing widespread intelligent life. If the Filter is behind us, then while that is not proof that there are no impassible obstacles in front of is, we have no particular reason to believe that there are impassible obstacles in front of us. That is in stark contrast to what has been the scientific dogma for the past several decades, which is that there is nothing special about us whatsoever, which does give us reason to believe there are impassible obstacles in front of us. To be able to put the filter way behind us is still a real change.

It depends on how fully the initial Great Filter explains the lack of observed exolife. It may not be a binary thing.

There could be one factor, or several. What matters is if the species can or cannot survive at the end to spread out or at least to make their presence detectable.

This aggregate of 'filters' is what's important.

Although it's science fiction, the second book from the "Three Body Problem" series by Cixin Liu offers an intriguing idea he labels as the "Dark Forest". The gist is that the primary motivation for all civilizations is survival and other civilizations are a threat. This Quora answer gives more detail, but I highly recommend reading the books; there are many compelling science-based ideas within it.

https://www.quora.com/What-is-the-Dark-Forest-Theory-of-the-...

Why would anyone want to spoil the books for themselves?

I spoiled this book for myself, and it was still fun. There was a lot of dramatic tension as I waited for all the characters to realize the horrifying things that lay in wait.

That's one way to go about it but it might be a bit simplistic and there's no reason why cooperation wouldn't work out for some civilizations as well. To completely hide one's signals is both hard to achieve and not necessarily beneficial. For example in ancient times there were blooming trades between empires which would not have been possible if every civilization just thought about hiding themselves. I was not a fan of "Three Body Problem" from its beginning.

The article is interesting but I don't think we can draw too many conclusions yet due to Kepler's observational biases. For example, the similar size pattern seen may only apply to closely packed systems rather than more widely spaced ones, and we don't have a great deal of information on the latter type.

Only if you assume solar systems with advanced life need to model our solar system, which I'm not sure is a foregone conclusion yet.

Re: the solar system we live in seems more unusual

We and we alone have the one and only Trump ;-)

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