Originally Posted by Stingray
A large part of the hilariousness of this whole convo is that he refuses to simply give a definition of what he thinks 3D means. Instead, he'll throw out Wikipedia links, discuss how you're arguing not with him but the industry or textbooks, or speculate about how you must work at Walmart or a gas station (likely the night shift).
Regardless of that…through his posts, one can mostly put together the pieces of the puzzle and figure it out. He seems to think that the critical piece to a game being 3D is that it features levels/maps that make heavy use of all 3 axes. For example, in his world, Doom isn't called "2.5D" because it uses 2D sprites to represent objects (which is why most people would call Doom "2.5D"). Nope, it's called "2.5D" because its levels/maps are all single-level and you can't fire your guns at an up or down angle. The thing that still mystifies me, though, is that with his definition in mind, he'd think Ultima Underworld was the first 3D game. Games as far back as Zaxxon (1982) or Star Wars (1983) should be equally 3D under that definition.