@sccrowell
Humanoid traits are such a specific and random occurrence of evolution. The probability of something evolving the exact same structure that happened to work the first time on Earth for us, and therefor coded into our genome as incredibly low even if they came from a similar planet and ignorant at best. And keep in mind this is all assuming that these aliens are not in a gas or energy form, etc. The possibility or life is endless and our scope of what can potential harbor life (carbon based, H20, etc.) is extremely narrow and only able to reference what very little we know and understand about life in reference to the universe.
We’re very stupid for the most. Trying to tackle the universe and existence is like a toddler attending an MIT calculus class.
To sum it up. Earth and everything about is very unusual and unlikely. I think this beautiful video explains what I mean.
David Deutsch: What is our place in the cosmos?
P.S. To answer everyone else’s fears of aliens, I think these are the ones to be afraid of.