What a joy — pun intended — to co-host season 3 of The Joy of Why alongside (metaphorically if not physically in space or time) my pal Steve Strogatz. When Steve was considering the title The Joy of x for his 2012 book, he dashed me a note, asking, “What do you think? My wife hates it.” I loved it. I thought the title was witty, hilarious for its reference to the 1970s sex manual...