Well, I've thought it out, and I will concede that voiced and voiceless phonemes are also an example of 'polar opposites'. Add phonotactics to grammar and math. Also particle physics.
It's still not a social science.
But didn't Hegel tell us that thought moves through a cycle of thesis/antithesis/synthesis, where the synthesis takes elements of each of the preceding notions, in something akin to the following manner? And did not Karl Marx dictate that, in addition to ideas, entire social and economic classes can and do operate in the same fashion, and that that is the base of history?
Thesis: Obnoxious Obama Hacks
Antithesis: Obnoxious Romney Hacks
Synthesis: 2012 Board
Simple dialectical materialism, the science of history.