EVERY WINTER, the season’s most confounding species emerges: the Male Nojacketus. On that first freezing day, you can spot him standing on the subway platform or hoofing it to Starbucks, nonchalant in his meager button-up shirt. Even when this foolhardy creature can see his own breath, he may not don a coat, or even a pair of pants (Male Nojacketi adore shorts, especially of the cargo variety). Scarfs or gloves? He would never stoop to such compromising accessories. The most extreme variety of the species will bare his toes in flip-flops on days that could easily end in snow.

What...