I believe the great filter is the jump from single-celled to multi-celled life.

I wish, but no.

Not until I see a real one walking past in front of me. Same goes for "spirits".

We are the aliens. We conquered the planet, destroyed the biosphere, and will soon be gone.

Yes, the universe is too large and we find life everywhere we look on earth (extremeophiles) and have tantalizing evidence of life in the solar system. I even think that we don't understand intelligence, and that a non terrestrial intelligence has developed somewhere.

I don't think they are abducting humans or making crystal skulls

I believe they're out there. I dont believe theyre cool Star Trek aliens flying around in spaceships and shit.

Its fun to think about though, and could be real.

No but i want to. I just havent seen any credible evidence. shrug

What humanity has dubbed "aliens"? No.

Extraterrestrial creatures/other lifeforms outside our galaxy? I don't know. We don't have enough data to prove it true or false yet.

Do they exist? Somewhere in the universe? Likely.

Are we in (or subject to) contact from them? Don't think so.

With one exception.

In the sense people mean when they ask that, no. It's gods and spirits for people afraid to just believe in gods and spirits.

In the literal sense of if life exists anywhere except Earth, the consenses is yes, it should. Although even there you have to wonder. The stars are awfully quiet and uncolonised-looking.