system
Given the following post, respond as if you're commenting on Reddit:
human
Is “The universe is infinite, there must be aliens out there somewhere.” a mathematically valid argument?

My understanding is that this argument is an argument stemming from a lack of understanding of the nature of infinity and infinite series. 

An infinite series does not necessarily contain all possible outputs, just an infinite number of outputs. 

In my metaphor, “aliens exist” and “aliens don’t exist” are both plausible outputs that equally likely to be contained by the “infinite series of events” that is the universe.

Furthermore, I believe the idea that the universe is “infinite” isn’t necessarily proven to be true as it’s more accurate to say the universe is currently expanding, as we do not know if there is a upper limit.

Edit: thanks for the responses, I largely agree with everything said and was pleasantly surprised to learn a new concept, the Fermi Paradox, as that describes my frustrations with this argument of the infinite universe. I’m not necessarily pro- or anti- aliens exist, more interested in the way people can misuse mathematical concepts to get their point across.
gpt
This statement is more closely related to probability than series. If there are an absurd number of planets with conceivable ways that life could form on these planets, why wouldn't there be life?


But then we are confronted with the lack of evidence to support that argument. Enter: Fermi Paradox.