Remember, the multiverse is the currently favored prophylactic against the theistic implications of cosmic fine-tuning.
You might think fouling your own environment with lots of toxic smog is a poor indicator of intelligence.
The best available science, including a new paper by Guillermo Gonzalez, demonstrates that supporting life on a hypothetical exoplanet is much, much tougher than NASA suggests.
NASA released an image, an "artist’s conception," that made Gliese 581g look like quite the garden spot.
It’s like some of these guys are conducting a disputation in their head against the ghost of childhood religion.