Our quadrennial presidential sweepstakes regularly provides textbook studies in contrast. And 2016 raises the bar in disparity. Red and blue. Left and right. Hot and cold. Up and down. Good and bad. Boy and girl. Pro and con. Loud and soft. Rain or shine. Fish and fowl. Dumb and dumber.

Perhaps the only fact that supporters of both major party candidates can agree is that differences between the two do exist. Donald Trump is a Gemini and Hillary Clinton a Scorpio. He’s 70 years old while sh...