Quote Originally Posted by kyoryu View Post
Most characters in most fiction are just plain vanilla humans, with no special abilities, and yet they are still very distinct.
I'm going to challenge you on that and say that no, they aren't all that distinct, and that there isn't even room for them to be all that distinct.

Why? Because empirical factor analysis on how human personality traits correlate does not support an infinite or even large number of independent dimensions to it. Using HEXACO as baseline example, we have six dimensions. From that, by varying each dimension between low, middle and high result, we get 3^6=729 personality archetypes.

Now, you might argue that the variance within dimensions is more granular than that, and that's how we'd get a much larger amount of different possible people. That would be true, but only in a technical sense that doesn't make much practical difference. These colors are all of a different hexadecimal value, but how many do you see, nevermind have distinct names for? Telok's findings in the "Sweetspot for chance of success" thread becomes relevant here. People are good at noticing difference between zero and none, and 90% versus 10%, but middle values are hard and 60% versus 40% is regularly considered 50/50. Minor variation, especially in middle results, is lost to everyday observers.

Now consider if I took a deep dive in TV Tropes and caught you 729 pages worth of archetypes. How much of fictional characters you think that'd cover? I'm reasonably sure a fraction of that would be enough to cover vast majority of popular characters. Because they aren't even that distinct in personality and motifs.

Furthermore, there is a practical limit, relevant to roleplaying games, that has to do with player skill. It takes effort, from the confines of your own personality, to convincingly play someone of different personality. So, do you have any confidence that a player showing up to your table would be able to play even 729 different personalities? Hell, can you name a professional actor that's even come close to that number? Indeed, many professional actors notably play same kinds of roles over and over.