Millennials! You’ve heard of them, right? Judging by the relentless media inquiry, you might suspect they are an alien race, landed from the future or outer space or Brooklyn, whom we must now dissect sociologically. As with every successive generation, at least since the Baby Boom, there is a widespread and thumb-fingered effort to get a grip on just who these young people are. National news magazines do cover stories. Pollsters track their attitudes. The Pew Research Center offers a quiz: “How Millennial Are You?” And everyone tries to fold 73 million young people, ages 18 to 34 or thereabouts, into a single box. They’re self-absorbed. They’re pampered. They’re socially conscious. They wear pajamas in public. They’re creative and entrepreneurial. They’re this or that, or that or this.