TheWayofPie
Explorer
It's a really weird, really old issue.
When D&D was naught but a misfiring neuron in Dave Arneson's brain, there was a not too popular wargaming hobby, and, since it was essentially historical reenactment on sand tables using tin soldiers, "realism" was a highly coveted - and very elusive - quality.
So, when various innovations passed through the minds of Gygax & Arneson - in what order, thanks to legal battles, we'll never know for sure -and emerged first as Chainmail, then D&D, there was a harsh line of criticism of hit point gain with level as profoundly unrealistic. If hit point damage represented the destructive force imparted by a weapon on it's target - as the weapon tables, with bigger weapons doing more damage, and STR mods would seem to indicate (and as the prior use of hit points in the Ironclads wargame would also imply) - then the only way a character could gain hps would be to become larger, or change it's material composition.
So D&D characters either grew to giant size, or went from glass to flesh, to wood, to stone to iron to vibranium or something - both of which would be ludicrous.
EGG defended his court-awarded-full-custody brain child with an exhaustive treatise, in the 1e DMG.
It seemed to quiet the critics, or maybe they just died of lead poisoning or old age.
For about 30 years it stood as the sole official explanation of what hps represented. It still does, actually: no other has been officially offered, nor has anything official contradicted it.
Yet, c2008, it became fashionable to criticise D&D for /no longer/ modeling hps solely as destructive force vs material strength, "as it had always done before."
When confronted with EGG's 30yo old treatise, they reacted - and are still reacting - as you see here.
Even out of all this wackiness, though some interesting developments have come. My favorite is the Highlander explanation of hps: adventurers are a supernatural race apart, with the power to absorb the life force of their slain foes (as XP) to increase their own power (levels) & life force (hp).
This is a very educational post.
I can honestly say I'm very interested in slowly evolving a character into a full bodied vibranium based hero, transcending their mortal limits.