Because of Krypton's high gravity, radiation levels, and other characteristics that made it inhospitable to advanced life forms, when proto-life arrived on Krypton (aboard ejecta from cosmic impacts on an inhabited planet far away-- see "panspermia hypothesis"), it stagnated for perhaps billions of years, until it evolved a most remarkable adaptation: the ability to directly shape the implicate order to the organism's own needs. To understand this, one has to grasp that consciousness (and here, "consciousness" is of a sort that is possessed by a unicellular organism) and the nature of the environment are reciprocally determined. "Consciousness" and "environment" mutually create one another in a sort of self-oscillation. In a sense, then, it's all one thing. Everything is "consciousness," and it is really true that by changing your mind, you can change the world around you. Indeed, at bottom, there is no difference between the two. It's all "mind," and instead of changing "your mind," you may be said to be "changing Mind." And by changing Mind, you locally alter the laws of physics!
Actually doing this is harder than it sounds, and yet, Earthlife does it all the time.
But Kryptonian life had to do it better. On Earth, conditions are hospitable enough that the most efficient way for life to copy itself is usually to just adapt to conditions as they are. Altering them at a fundamental level is usually a waste of resources, and organisms that invested too heavily in this ability were out-competed by others.
Kryptonian challenges, however, necessitated a far heavier investment in this ability to directly manipulate the implicate order that creates physical reality.
So what I am saying is something like this: It is not that Superman is so strong and invulnerable and so on according to the laws of physics that usually govern Earthlife. It is that he, like all advanced Kryptonian life, has an inborn psychic ability to alter the laws of physics in his immediate vicinity. The exercise of this ability is quite reflexive, operating without his higher awareness. It is not qualitatively different from what human psychics and miracle workers have been known to do. He is just much better at it.
So when you say it's impossible for a person's eyeball to repel small arms fire, no matter what planet he's from, you're right. What Superman does is change what is possible, albeit on a very limited, very local level.
Why isn't this ever explained in the comics and movies? Too boring.
Now post those nude pics like you promised.
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