 Without clear support for the rule utilitarian reading of secondary principles, it seems that Mill’s main claims about secondary principles are not inconsistent with act utilitarianism. Moreover, it is clear that Mill thinks we need to depart from otherwise justified secondary principles in an important range of cases. Though Mill does not treat secondary principles as mere rules of thumb in utilitarian calculation, he does not think that they should be followed uncritically or independently of their consequences. He thinks that they should be set aside in favor of direct appeal to the principle of utility when following them would be clearly suboptimal or when there is a conflict among secondary principles.