Suddenly standing alone in the room, I begin by imagining humanity banding together and blue winning in a landslide, and I feel a rush of pride. Red is the genocide button. Blue is the “save humanity from this nightmare” button. I know what kind of person I am. As my hand hovers over the blue button, I can’t help but imagine a gun pointing at my head with a bullet in one of the chambers. I feel a surge of fear shoot through my body. Then I think about all the other people staring at the blue button and thinking the same thing. Surely some of those who initially decided to press blue will succumb to the fear. It starts to feel like a gun with two loaded chambers. A stronger pulse of terror. The more I think about it, the more I worry about other people thinking about it. My heart races. Then I look at the red button—a gun with no bullets in it. A glorious feeling of relief washes over me. Will I hate myself forever if blue wins because enough others were better and braver than me? But don’t I owe it to my family to protect myself? One vote won’t change anything anyway, right? It’s all irrelevant because the mammal I live in has already made up its mind. I wince and press red.

Everyone in the world has to take a private vote by pressing a red or blue button. If more than 50% of people press the blue button, everyone survives. If less than 50% of people press the blue button, only people who pressed the red button survive. Which button would you press?