That's assuming a technological civilization's natural progression is towards space travel, which may or may not be true. The Aztecs were way "behind" when explorers first discovered them, but were doing pretty fine.

Indeed and wouldn't they have been "interrupted" they very well might have developed further towards space travel or is there anything to suggest that they wouldn't have progressed further technologically?

It might stop existing as a technological civilization, but it might continue existing as a civilization that's lost access to its technology.

Unlikely, as on the astronomical time-scales involved, that implies that some rare risk will eventually wipe them out - asteroids, pandemics, resource depletion, collapse.

> What happens when a technological civilization 'doesn't last long enough'? It stops existing.

But it did exist, which is clearly the point here.

It's not clearly the point at all. If the solution to the Fermi paradox is 'they existed at one point but stopped before colonizing', then that implies they don't exist now and is why we don't see them.

What is clear is that I did not take a large enough quote from the post I was replying to. Here is an expanded version:

>> Both York and Teller seemed to think Fermi was questioning the feasibility of interstellar travel—nobody thought he was questioning the possible existence of extraterrestrial civilizations

>What happens when a technological civilization 'doesn't last long enough'? It stops existing.

(your emphasis.)

Your observation that a civilization does not exist after it has ceased to exist does not "question the possible existence of extraterrestrial civilizations". To the contrary, unless we assume the author intended to state an empty tautology (which would be too pedantic an assumption to take seriously), then the statement I have just quoted is actually predicated on the assumption that it is possible for them to exist. So, when Fermi suggests that civilizations tend to fail before they colonize the galaxy, he is not questioning their possible existence.