[mym1990]

We certainly wouldn't be where we are today, but it's extremely speculative to know where we would be...could be worse or better. One problem I see with where we are now is that once the ball of inertia of group activity gets going, it is very very difficult to get it to go in another direction.

[baking]

I think the idea is that is certainly feasible for an alien civilization to go from steam power to fission in under 200 years. What makes it a "great filter" in my mind that the idea that the climate change clock might start ticking long before they are aware of it and that there could be a hard time limit.

Most other possible filters aren't as tricky. Sure stars explode, planets get hit by asteroids, and species go extinct, but those are pretty much chance events.

[mym1990]

I think at the end of the day, planet destruction, whether it be by asteroids or global warming or anything else…is assured no matter how small the chance is. So the game is multi planet/galaxy settlement before time runs out.

The hilarious part of it all is that we have a sample size of 1(and almost not even one since we haven’t hit the filter yet).

[baking]

For Homo Sapiens, this is our big risk. But from the aspect of the Fermi Paradox, I don't think it can be a great filter. Obviously a civilization must be multi-planetary to make contact, and once it is multi-planetary it is no longer threatened in this way. But statistically, it is still low probability.

As an analogy, you need to have fire insurance, but most houses in your neighborhood don't burn down (unless you live near wildfires which for the purposes of the analogy I think we can exclude.)

I think the pessimistic argument goes something like this. There is at least one great filter, probably more. Through extreme luck, we have gotten past all but one of them and are very close to the last. We may very well be the only advanced technological civilization in our galactic cluster, and if we don't extend into space soon we are at high risk of being extinct or facing societal collapse.

It's an imperfect analogy, but what I'm saying is: If I have a lot of neighbors, I don't really care if they all have fire insurance. If I'm the only house in the neighborhood, I really need fire insurance.