[spydum]

you have to wonder if there is some magnetism in people which draws them to polarizing topics (both to build polarizing arguments, and to engage in them). Maybe it's as simple as we are highly competitive, and in the absence of competition, we create rifts just so we can establish who is greater?

[JoeAltmaier]

Simpler: people like to argue. Some multi-dimensional topics its hard to find a single definitive answer. Those topics, you can argue about forever.