You know, all the snarkiness and sarcasm about my defense of the cosmology having some roots in history really isn't necessary.
Note that I never said the outer planes were a medievalism, just much of the Great Wheel Cosmology, and by "Great Wheel Cosmology" I do mean the entire traditional D&D cosmology from inner to outer and everything in between.
The elemental planes most certainly were, concepts of planar layers were, and there were concepts similar to the transitive planes. As for outer planes, yes only Heaven and Hell (and maybe purgatory) would show up in medieval or renaissance cosmologies. Even radiating from inner to outermost planes is similar to medieval cosmologies (although they typically had Earth in the innermost part). If you omitted all the outer planes except Heaven and Hell (or marked all the upper planes as heaven and all the lower planes as hell, ), a depiction of the Great Wheel Cosmology to a medieval scholar would appear novel, but not totally incomprehensible. Showing the same scholar what appears to be this New Cosmology would be showing him something totally beyond his reckoning.
The most important part of that was the elemental planes, what is definitively getting the axe in this version of D&D, is a medieval concept, the old D&D cosmology was closer to "historically" accurate than this mish-mash they are producing now, which sounds more like a list of raiding zones for an MMORPG expansion than an actual planar cosmology.
Geron Raveneye said:
What wingsandsword is trying to point out is that the current cosmology was and is (with slight modifications for each edition) the default cosmology for AD&D. If you don't believe me, read the threads that deal with the topic, there's enough material in there to show it is. What he dislikes is that they are chucking the default cosmology, which has 30 years of roots and traditions with AD&D, for something that is supposed at once simpler AND more adventure-friendly, essentially cutting off every older AD&D player at the knees in terms of shared continuity of their game and backwards compatibility.
Exactly, the cosmology of D&D has been a constant for almost three decades (since the 1e DMG in '79 is the earliest version I can dig up), and every official setting was presumed to be a part of it unless explictly said otherwise. In the 2e era, Dark Sun internally said it wasn't a part, but other settings presumed it was, and Mystara never even pretended to be a part (but Mystara was definitely a special case). In the 3e era, they retconned Forgotten Realms into a new cosmology, but at least that cosmology was much the same, just jumbling up the order of planes and making some deific domains into separate planes.
Now though, the classic cosmology won't even be the default in the PHB, someone who has been playing D&D since the '70's and enjoys planar adventures will find 4e far more of a jump in differences in edition than the big 2e to 3e jump. 3e might have changed a lot of the mechanics, and some bits of "fluff", but it did try pretty hard to maintain historic continuity with the rest of D&D. Now it feels like they are trying to intentionally break that continuity.