My new blog post looks at the history of planar design development in AD&D:  https://grodog.blogspot.com/2025/03/brief-history-on-development-of-planar-cosmology.html

More to follow!

Allan.

I like this article quite a bit, but I'm also a sucker for any discussion regarding cosmology in the context of a setting, and planescape as a whole really captures my imagination.

It's fun to see how it sort of evolved as planes got added, likewise seeing the schema of it change as the alignment system came to be as it is. though I must admit I am quite partial to the old single axis system of Law Vs. Chaos as Paul Anderson envisioned it.

An interesting carry over/relic of Law Vs. Chaos is that based on my reading and much of watching Aj Pickett I've come to believe the only two alignments that matter are Chaotic Evil, and Lawful Evil, since they are really the only two forces poised to rule the multiverse, both in a stalemate with one another.

I quite enjoy that cold war style tension about the setting, though it does make me vastly less interested in the upper planes as I find them rather boring. 

This is an interesting read if only to see the parts where the business intrigue involved in TSR evicting Gygax got in the way of developing the world (see: Shadowlands.)

As a whole, the planes are probably my least favorite aspect of D&D. The problem is that the D&D universe is at it's most wondrous when you have only heard the pitch. The act of exploring any of this space makes it less wondrous and starts to introduce funny flavors to D&D's core flavor. I won't necessarily say this is always true (I haven't played every D&D campaign ever), but my general experience is that the planes are best left as an unopened Pandora's Box, so they can add mystique and lore without adding flavor conflicts. The instant you open the box, things start to taste funny, and the more you open the box, the funnier things taste.