Many people use 'logic, reason & rationality' to justify their beliefs by mistaking attempts to think critically with objectivity itself.
The body you experience is also home to trillions of other living organisms with minds of their own, which brings up interesting questions about the self, reality and free will.
What can we do that other living things can't, or aren't doing that they can, and why not? Is there something about humans holding us back?
Season four of the science fiction series Black Mirror reveals the shows unfortunate underlying nihilism and human fatalism.
From God to Nature, human beliefs in external, omnipotent and omnipresent forces are essentially the same and have lead to authoritarianism and human-on-human force.