There is also the theory that has been floated that we are the most advanced firm of carbon life specifically because we are so galactically young. The theory states that older civilisations would have (possibly) depleted their own resources and gone extinct.

Basically, the thought is that life, in and of itself, is destructive. Even while trying to better ourselves, we are constantly doing just as much, or more, harm than good. And in our pursuit of galactic discovery we aren't interested in advancing or abilities to sustain life long enough to make THE discovery.

Intelligent life seems to have the innate belief that we are as advanced as we need to be to make the next step as it pertains to discovery of other intelligent life.

Keep in mind that we still do not understand a large portion of life on our own planet. And how much of that life is eons older than we are.

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