In latter-day discussions on corporate morality, duties of commission are fiercely debated. Moral institutionalists argue that duties of commission—such as a duty of assistance—overstep the boundaries of moral duty owed by economic agents. " Moral institutionalism" is a newly coined term for a familiar position on market morality. It maintains that market morality ought to be restricted, excluding all duties of commission. Neo-Classical thinkers such as Baumol and Homann defend it most eloquently. They underpin their position with concerns that go (...) to the core of liberalism—the dominant western political theory that sustains the ideals of both the free market and the free, rational person. Those authors claim that liberalism calls for a fully differentiated market because it resents the politicization of the market. Fully differentiated markets exclude duties of commission. They also claim that full differentiation of the market closes the troublesome gap between moral motivation and moral virtue. Full differentiation redeems the promise of "easy virtue". In this paper moral institutionalism will be rejected from a Kantian point of view, mostly inspired by Herman's thesis on the invisibility of morality. Liberalism may perhaps ban the politicization of the market; it does not forbid its moralization. The idea of a fully differentiated market must also be rejected because it is either morally over-demanding (to the morally autonomous person) or morally hazardous (to the person with failing moral motivation). Contrary to what the moral institutionalists claim, right action, morally, is actually quite difficult in fully differentiated markets. (shrink)