"Some people are clearly more altruistic than others. But even these super-cooperators can’t do all the heavy lifting alone."

"Haphazard or individual-level efforts to be helpful are rarely sufficient to keep cooperation going in a larger population. For one thing, a cooperator surrounded by noncooperators will usually stop being helpful—for who wants to be a chump? Yet devolving to an 'every man for himself' dynamic is injurious to all. That’s no way to fight a plague.... We also practice punishment and ostracism, both of which can, in the right circumstances, foster cooperation. Shunning transgressors comes naturally to us precisely because, in our ancestral past, it was useful for our collective survival.... Indeed, President Joe Biden announced a broad series of interventions last month, including requiring all employers with more than 100 employees to mandate vaccination and doing the same for federal workers and others.... We do not need to see these actions in a negative or even authoritarian light. They are not simply the workings of our political system. They are rooted in our ancient past, helping us survive. Seen from an evolutionary perspective, putting our thumb on the scale of the COVID-19 response allows our natural impulse toward goodness to flourish. And such efforts are in keeping with our fundamental instincts to be altruistic and cooperative in the first place. As Albert Camus argued in his novel The Plague, 'What’s true of all the evils in the world is true of the plague as well. It helps men and women to rise above themselves.'" 

From "Sometimes Altruism Needs to Be Enforced" by Nicholas A. Christakis (The Atlantic).