A new semester of teaching my MBA class “Reimagining Capitalism” began last week. My colleague George Serafeim and I have over 300 people taking the course in four classes – nearly a third of the second year class. By way of introduction I asked everyone in my classes to send me a paragraph about why they were taking the course – particularly given that they could be taking obviously useful courses like “Power and Influence” or “Real Estate and Private Equity” instead.

In class this week we’ve been arguing about whether publicly traded firms have a moral duty to maximize profits. It’s a contentious idea, but my own belief is that firms only have such a duty when markets are genuinely free and fair: genuinely competitive, properly priced and open to all comers. When this is not the case, to focus on nothing but profit maximization is, I believe, to betray the very commitments to freedom and prosperity on which the legitimacy of capitalism depends.