In economics, “social cost” is really a euphemism for the destructive consequences of capitalism. Milton Friedman famously referred to them as “neighborhood effects,” and today it is more common to call them “market failures” or “externalities.” Regardless of what we label them, they are the secondary or indirect effects of some market transaction or transactions. And because I am convinced of their urgency, today I want to call attention to the social costs of social media and the internet in …