The Lessons of Homo Economicus

I just read an interesting new paper by UCLA law prof Lynn Stout titled "Taking Conscience Seriously," in which she laments the failure of economics, law, and business professors to recognize the ubiquity of altruistic behavior in our society.  She begins with this everyday example:

Imagine that you see a dozen pedestrians walk by a sleeping homeless man who is lying next to a sign that reads, "Please Help" and a cup that contains a few dollar bills. Many people might conclude they are observing selfish behavior when no one puts any money in the cup. Few would recognize that they are witnessing multiple acts of unselfishness as person after person walks by without stealing from the helpless homeless man.

The "rational maximizer" known as Homo Economicus "does not worry about morality, ethics, or other people.  Instead, Economic Man worries only about himself, coldly and calculatingly pursuing whatever course brings him the greatest material advantage."  This is an unrealistic view of the human person, but it is a view that takes root in part because we "tend not to notice common forms of unselfish behavior."  One problem she flags is the absence of altruistic behavior in law school pedagogy:

Formal law is usually brought into play when cooperation breaks down and individuals become embroiled in conflicts requiring outside resolution.  This makes it easy for law students who spend hours studying case law -- the documentary debris of crimes, horrible accidents, difficult divorces, and bitter contract disputes -- to conclude that selfish behavior is the rule.

I rarely grapple with this question, but I should:  what are the unspoken lessons about the human person imparted by the cases I teach?

UPDATE: Patrick O'Donnell recommends some additional resources for those interested in these questions:

Amartya Sen long ago addressed her principal concerns in 'Rational Fools: A Critique of the Behavioral Foundations of Economic Theory,' Philosophy and Public Afffairs, 6 (1977), reprinted in his book, Choice, Welfare and Measurement (1982).  See too Sen's Ethics and Economics (Oxford, UK: Blackwell, 1987). Indeed, a better picture of the state-of-the-art (and science) on this question is Sen's recent Rationality and Freedom (Cambridge, MA: Belknap Press of Harvard University Press, 2002). What is more, her characterization of economics strikes me as rather tendentious: see, for instance a work well-versed in neo-classical economics: Partha Dasgupta's An Inquiry into Well-Being and Destitituion (Oxford, UK: Clarendon Press, 1993). Two excellent titles treating these questions in a fundamental manner are missing from her bibliography: Daniel M. Hausman and Michael S. McPherson, eds., Economic Analysis, Moral Philosophy, and Public Policy (Cambridge, UK: Cambridge University Press, 2006 ed.) and Elizabeth Anderson's Value in Ethics and Economics (Cambridge, MA: Harvard University Press, 1993). Not unrelated to these topics are questions broached in Donald (now Deirdre) McCloskey's The Rhetoric of Economics (1985) and Knowledge and Persuasion in Economics (1994).