We are the only life form of the univers. Not even the only intelligent, but the only one. My arguments are:
Life is absolutely everywhere on earth. There is not a single isolated island or deep trench in the ocean that is not covered by life. If life can live elsewhere, univers would be covered by life. Some bacteria would have been ejected into space by some cataclysme and had colinized nearby planets. Kind of Fermi’s paradoxes.
Antropic argument. Our universe is suitable for life because if it weren’t, we simply wouldn’t be there. Add it to Okam razor. If a smaller, simpler, universe could handle life, we would be in that one. Not our current one.
“Our universe is so huge, so there must be other life form” is not the right statement. Our universe is so huge because it is the smallest universe where life could potentially appear.
Only my opinion, not a scientific demonstration.


You exactly spot it. “any scenario can only arise from the simplest system that could cause that scenario to arise”. Nature is lazy and don’t like spending resources for nothing.
Again, it is my opinion, and I posted it here to challenge it.
If you have examples or argument against it, where scenarios did occured in over complex system, i’m interested 🙂.
I think your argument is also an argument against destruction of complexity back to simplicity.
It’s also using circular logic. You’re assuming the universe only has the complexity to give rise to one form of life and therefore the universe must be simple enough to have only given rise to one form of life.
Nature takes non-optimal “non-lazy” approaches all the time.
For example, the wiring of the eye in vertebrates is “backwards”, with the optic nerve passing in front of the retina, blocking light and creating a blind spot. It takes more resources and more energy to do it backwards than it would to wire it up “correctly”.
Complex natural systems often get stuck in local minima that prevent them from reaching true optional states. Take the fact that we haven’t experienced vacuume collapse yet as another example.