In Dreams from My Father, there is a recurring pattern whereby Obama’s growing sense of conviction is sharpened in opposition to the confusions and self-delusions of others, and the book’s two main encounters with other mixed-race people fit squarely within this narrative.

The first encounter happens in 1979. In his freshman year at Occidental College, Obama meets a green-eyed, mixed-race student named Joyce and suggests they go to a Black Students’ Association meeting together. She’s affronted. “I’m not black,” she says. “I’m multiracial.” She has an Italian father and a mother who’s part African, French, and Native American. “Why should I have to choose between them?” she asks.

Obama is affronted in turn—angry, even—but then he reflects on the similarities between Joyce’s response and his own earlier, more immature attitude.

Unlike her, he stopped advertising his mother’s race when he was around twelve, suspecting that, whether or not it was conscious, the reason he was telling white people was to ingratiate himself with them. He mentions the split-second adjustments of strangers, searching his eyes for evidence of a divided soul, for “the ghostly image of the tragic mulatto trapped between two worlds.”

Going against the grain of people’s assumptions, highlighting a proximity to whiteness when you don’t pass as white, generates a special sort of anxiety. In my experience, the response to hearing about my mixed heritage—besides surprise, usually muted—is often tinged with pleasure. You go from being purely other to only partly so. Which is why it can be discomforting to say that my dad grew up in Devon. To emphasize that part of myself feels like erasing the other. I feel too few and too many.

No one should have to choose between their parents or the different parts of their heritage, but what I think Obama’s college friend Joyce reacts to—what upsets her so much—is that the choice has already been made for her. However many times she says multiracial or mixed race, she can’t choose how to be seen.

So when Obama identifies her as black, expecting the same acknowledgment in return, she balks at it because it reminds her of how little choice she’s ever had. No longer Emerson’s dreamed-of “transparent eyeball,”⁹⁰ unseen and observing, she becomes a body. A body that feels unreal to her. Alien.

The second encounter takes place in 1988. A 27-year-old Obama has flown to Nairobi to meet his Kenyan family. By coincidence, his half-brother Mark—studying physics at Stanford—is also visiting. They decide to go to an Indian restaurant and during the meal Obama asks him how he feels about Kenya.

“I don’t feel much of an attachment. Just another poor African country,” says Mark.

“I should have stopped then,” Obama writes in his memoir, “but something—the certainty in this brother’s voice, maybe, or our rough resemblance, like looking into a foggy mirror—made me want to push harder.”

He asks his brother if he ever feels like he’s “losing something,” but Mark is smart. He can see where this is going: “You think I’m somehow cut off from my roots, that sort of thing.”

They’ve had the same experience of an absent father, but where it makes Obama “mad” it only leaves Mark “numb.”

Mark defends his numbness. Beethoven’s symphonies and Shakespeare’s sonnets still move him. “Who’s to tell me what I should and shouldn’t care about?”

For Mark, like Joyce, having a mixed identity means not being told what he should like, being able to choose. “Understand, I’m not ashamed of being half Kenyan. I just don’t ask myself a lot of questions about what it all means. About who I really am.”

Obama sees his brother hesitate for a moment, “like a rock climber losing his footing,” before he recovers and asks the waiter for the bill. “What’s certain,” says Mark, “is that I don’t need the stress.”

Mark has closed off a part of his experience, turning away from his father’s heritage. Looking at him is not just like looking in a foggy mirror—his way of thinking is itself foggy. Obama, though, sees him with the same ruthless clarity he would apply to making his own identity, as just another confused brother in denial about his past.