I just signed up to be a mentor at my law school, and did something that is atypical for me: Display a preference for female law students. It even surprises me when I look at that sentence, since my entire career as a columnist has been dedicated to the proposition that gender, race, sexual orientation, religion and all of the other epidermal things that form our identity are less important than the intangibles of brain, values, heart and capacity for endurance.