Wednesday, December 3, 2014

The Numbers Guy

I was talking to a friend the other day about what some people say was the real meaning of the "1d6 per 10 feet of falling" rule in original D&D. In short (per Frank Mentzer, I think), it was supposed to be 1d6 for the first 10, then 2d6 added to the first for the next 10, and so on; so a fifty foot fall was 1 + 2 + 3 + 4 + 5 = 15d6 damage, or an average of 52.5 points—not 5d6 (averaging 17.5).

He said, "that's too much math." I was flabbergasted.

He's a smart enough guy; how hard could counting to five, and adding five single-digit numbers, be?

But then I got to thinking about some of the mathematically illiterate statements I've read on reddit or stackexchange. Things like:

  • "A 3d6 bell curve roll is better than d20 because with a d20, you're just as likely to roll a 20 as you are to roll a 1." (And you're just as likely to roll a 3 as an 18 on 3d6—so?)
  • "I have 65% in my Drive skill, but I still fail one-third of the time... why?" (Because you're 1.67% luckier than the statistical average.)
  • "2d8 + 1d6 -2? That's too much math." (Adding and subtracting four numbers?)

I don't want to have to calculate the parabolic arc a missile takes when I fire it (taking wind resistance into account, of course), and I don't want to have to break out a calculator whenever I decide if I should attack from a higher or lower vantage point. I love how Lamentations of the Flame Princess simplifies encumbrance so I don't have to tally up every point of weight I'm carrying. But part of envisioning a world, even a fantastic one, is knowing that going up and down a hill takes longer than walking in a straight line, or that if I have only three arrows left, I'd better start looking for a fletcher.

Heck, even Candyland involves counting; how hard can it be for people ages twelve and up to do just a little bit more math than that?