Sometimes, the most important questions are the basic ones. Back in 2011, I argued that the most important question in the gay-marriage debate was "What is marriage?" The next year, Robert George, Ryan Anderson, and Sherif Girgis published a book exploring just that question: What Is Marriage?: Man and Woman: A Defense. But in the face of contemporary questions of transgenderism and gender identity, it turns out that we need to ask a yet more-basic question: what are men and women, and what makes them different?
A lot's been said about the case of Olympic decathalon Bruce Jenner's decision to undergo a "sex change" operation, and to call himself "Caitlyn." Unfortunately, a good deal of it has been sound and fury, signifying nothing: either cruel jokes at Jenner's expense, or accusations of bigotry for anyone who hasn't hopped on the transgender bandwagon. A better approach would be to soberly consider the underlying philosophical problems raised by transgenderism, and then suggest a positive way of responding to trans-identifying people. So that's what I've tried to do here, beginning with: