Many of the institutions of modern society, after all, are designed to enhance our natural capacities for cooperation, by punishing non-cooperators and encouraging the rest of us to pursue even relatively mundane collective actions, like paying taxes and getting flu shots. And so, when pandemics unfold, it's not just because peculiarly aggressive pathogens have exploited passively oblivious victims or because we've inadvertently provided them with ample transmission opportunities. It's also because our deeply rooted, highly nuanced capacity for cooperative action failed.