[zachalexander]

This is a great point – which I would paraphrase as, let's not worry about cosmic filters when we have a very tangible filter in front of us – but it doesn't follow that we're "provably not beyond the great filter".

The Great Filter is just the thing that explains most of why intelligent life is (or seems) so rare in the universe. It could be true, for example, that some cosmic event kills life before it becomes technological 99% of the time (= Great Filter), and also that, say, 60% of technological civilizations destroy themselves via destroying their environment.

[api]

Given that we have only one known example of intelligent life, we are the only thing we can base any predictions upon. Given that we have a provable filter in front of us, I think it's reasonable to assume that similar situations might occur elsewhere in the universe:

(1) An intelligence reaches a critical intellectual mass and begins to utilize the free resources that are present in its environment.

(2) In doing so it grows and develops exponentially.

(3) By the time it develops far enough intellectually to realize the problem -- exponential growth built on finite non-replenishable supply -- it's already too late.

We seem to have realized this problem around 1950-1970, and we have done very little about it so far. That's because huge complex systems are hard to change, and all the incentives point the wrong way.

[zachalexander]

Sure, but that's just a case for "ecological sustainability is a reasonable candidate for the GF based on what we know about ourselves." Which is a weaker statement than "we are provably beyond the GF". Provable implies strong evidence and certainty.