The most compelling image of Nelson Mandela's memorial was a still photograph of two young people, a young white woman and a young black man, holding each other, and using the South African flag to shield themselves from the rain.

And I had hope. And I thought about sex.

On the question of how much work there is to do to eradicate racism, I tend to slag a bit more optimistically than Ta-Nehisi Coates, but not too much more. As a white guy, I sense some institutional racism. I know there is more because I know I am not capable of sensing it all. I tend not to ruminate on it, and so it surprises me how frequently I do come across it.

A certified massage therapist in Hollywood, California of all liberal places, was oblivious enough to elucidate the differences between his black and white and Asian clients — simply because I was nice, and was white, and had asked him how long he had been practicing his art. This was Monday night. In the literal shadow of the venue where they hold the Oscars. I should have gotten up off the table and walked out, but I wasn't brave enough.

A massage is intimate enough. But it's an artificial closeness. This guy was fine with touching the bodies of black men and women — their money was as good as mine, apparently. He wasn't really sharing anything but his time and professional skills, or un-skills.

For a while, I've had a theory that sex is the ultimate racism-tester. If you can envision yourself sharing your most intimate moments with someone, chances are slim that you'll discriminate against them the next day. If you can't envision yourself having sex with someone solely based on their skin color or ethnic heritage, it is hard to believe that you will go out of your way to make sure that the same subconscious bias isn't crossing through the membranes that separate personal from professional. 87 percent of Americans support interracial marriage; about 15 percent of all new marriages are between people of non-same ethnicities. This is good data.

But how many Americans have actually had sex with someone of a different race? I couldn't find an answer. ("Dating" isn't sex.) And if you spend time in or read about the alternaverse of online dating sites and hookup apps, straight and gay, it's almost an overworn joke to notice how many white guys tell you that (sorry!) they aren't into black women, or how many gay guys will include "No Asians" in their profiles. (I think I've read like 18 Huffington Post pieces alone about that last anecdote.) This is real racism, blatant and banal, casual and even comfortable. For those who say that "people have their preferences," I would simply ask them whether it's worth broadcasting them simply to prevent the appearance of a picture of a black woman or an Asian man in your inbox. Because the fact that you do broadcast them is a way of telling everyone who happens upon your profile that you (sorry, don't mean to be mean) cannot conceive of a physical or emotional relationship with someone based on their skin color.

Now: Like attracts like. Underlying sexual attraction is complex biochemistry that doesn't lend itself to sociological theories. But I would wager that whatever biochemical forces guide us to attach with someone, social and psychological forces, all reinforced by our experience, play just as big a role. But no matter. You might agree with what I'm suggesting and still protest that there's nothing you can do to force yourself to want something you don't want. And I get that. Being openly supportive of those in interracial relationships and trying to acknowledge your own biases, however subtle they are, is a good place to begin engaging the question.

I began the day with the hopeful picture, and I ended the day with a pessimistic Buzzfeed link. Apparently, "One Direction Fans On Twitter Are Saying Insanely Racist Things About Lorde’s Boyfriend."

Because he's an Asian guy.

And she's white.