Peter started a discussion here. And Nick Rowe at Worthwhile Canadian Initiative, under the title "God and Man at Yale" has another one, with hundreds of comments. I'll add my two cents. This is a comment I sent to WCI actually.
I want an Intro. Course to show students "how to think like an economist," but I also want some time devoted to the limitations of such thinking. I used to teach the course with David Friedman's *Hidden Order* and Robert Frank's *Choosing the Right Pond*, so they could see how the same methodology - rationality plus equilibrium - could give you very different political-economic visions. But the methodology itself -whether wielded in support of libertarian or left-liberal politics - ought not to be accepted uncritically. So I would assign Dickens' *Hard Times*. The students hated the Dickens, so I dropped it and substituted Amartya Sen's "Rational Fools." I wanted them to understand how the phenomenon of "commitment", as Sen uses it, by which he means "counter-preferential choice" is a deep critique of the conception of rationality that economists use. Unlike the behavioral critique, which simply documents all the ways people make mistakes in maximizing, a Senian critique says that human beings are more than utility maximizers. As the late lamented David Foster Wallace puts the point in a discussion of Dostoevsky, "[Dostoevsky’s] concern was always with what it is to be a human being—that is, how to be an actual person, someone whose life is informed by values and principles, instead of just an especially shrewd kind of self-preserving animal." I don't think this deep critique cuts either right or left, but I think we do a disservice to our students by not exposing them to it. The fact is that most of them when they come to us are already "thinking like economists" in important and pernicious respects: they are cynical about the possibility of principled behavior, they are sure that behind every alleged "value" lies a preference, they are nihilistic about normative authority. The have been brought up, after all, in the age of "sophisters, calculators and economists."
At an AEA meeting one year long ago, there was a session on "Teaching the Principles Course" I attended, which was really just advertising for two new texts by the presenters, one of whom was Robert Frank. (The text he was introducing is the one I have used in the Micro split ever since - it's a great book.) Frank talked about how the book encouraged the students to be economic naturalists, and to apply the economic way of thinking to everything they came across. I asked a question: suppose a student comes to your office hours and thanks you for teaching him the EWT. He was in a long-term relationship and felt that he owed his partner loyalty, but that after learning that sunk costs shouldn't play any part in guiding one's choices, he decided - given that the net benefit of the relationship going forward was negative- that he owed his partner nothing, and consequently was dis-loyal. Frank seemed genuinely at a loss for a response and after the session sought me out to talk more about it.