Here's the abstract of a new paper seeking to explain Superman's powers.
Since Time immemorial, man has sought to explain the powers of Kal-El, a.k.a. Superman. Siegel et al. Supposed that His mighty strength stems from His origin on another planet whose density and as a result, gravity, was much higher than our own. Natural selection on the planet of krypton would therefore endow Kal El with more efficient muscles and higher bone density; explaining, to first order, Superman's extraordinary powers. Though concise, this theory has proved inaccurate. It is now clear that Superman is actually flying rather than just jumping really high; and His freeze-breath, x-ray vision, and heat vision also have no account in Seigel's theory.
In this paper we propose a new unfied theory for the source of Superman's powers; that is to say, all of Superman's extraordinary powers are manifestation of one supernatural ability, rather than a host. It is our opinion that all of Superman's recognized powers can be unified if His power is the ability to manipulate, from atomic to kilometer length scales, the inertia of His own and any matter with which He is in contact.
Really, what lessons do the Superman comics teach? It says that mankind is full of dull, pointless weaklings and evildoers who can only be stopped by a white ubermensch from another planet, who didn't work a day in his life in order to achieve his powers. Yeah, you could say he's a symbol of "hope," but not hope in human nature - hope in an all-powerful alien who saves the world daily so you don't have to get off your butt and act like a moral person. What sort of message is that?
Out of a recent conversation popped this interesting question: who was the first superhero? After a short discussion and a few guesses (Superman, Batman, etc), it was agreed that this might be the most perfect question to ask the internet in the long history of questions.
The earliest superhero I could find reference to was Mandrake the Magician, who debuted in 1934, four years before Superman, who was probably the first popular superhero. Mandrake's super power was his ability to "make people believe anything, simply by gesturing hypnotically". Does anyone out there know of any superheroes who made an earlier media appearance?
There's a related question that has some bearing on the answer to the above question: what is a superhero? There have probably been books (or at least extensive Usenet threads) written on this topic, but a good baseline definition needs to acknowledge both the "super" and the "hero" parts. That is, the person needs to have some superhuman power or powers and has to fight the bad guys. But this basic definition is flawed. Superman is an alien, not human. Batman doesn't have any super powers...he's a self-made superhero like Syndrome in The Incredibles. Or can a superhero be anyone (human or no) that fights bad guys and is superior to normal heroes...the cream of the hero crop? And what about a costume or alter ego...are they essential for superheroism? These are all questions well-suited for asking the internet, so have at it: what's a good definition for a superhero?
And there's (at least) one more angle to this as well...where did the idea of the superhero come from? As Meg suggested to me at dinner last night, was there a cultural need for a superhero during a super-crisis like the Great Depression? Or did the idea evolve gradually from regular heros (cowboys, space cowboys, etc.) to heros who were magicians (with special powers...it's not that much of a stretch to imagine a magician possessing supernatural powers) to classic superheroes like Superman?