Would theists become atheists if we found lifeform

[Mister Agenda]

It probably wouldn't bother most, as there's no scripture I'm aware of that comes right out and says there aren't other sapient species 'out there'.

There are certain arguments that come up now that would be refuted, but they're awfully weak in the first place, along the lines of 'how do you explain no aliens, checkmate atheists!'.

They're more likely to be challenged by the theology of the aliens, or their lack of it. The Abrahamic ones would have to try to figure out if the aliens are fallen or not, I think.