 There can be genuine moral dilemmas only if neither of the conflicting requirements is overridden. Ross (1930, Chapter 2) held that all moral precepts can be overridden in particular circumstances. This provides an inviting framework for opponents of dilemmas to adopt. But if some moral requirements cannot be overridden—if they hold absolutely—then it will be easier for supporters of dilemmas to make their case. Lisa Tessman has distinguished between negotiable and non-negotiable moral requirements (Tessman 2015, especially Chapters 1 and 3). The former, if not satisfied, can be adequately compensated or counterbalanced by some other good. Non-negotiable moral requirements, however, if violated produce a cost that no one should have to bear; such a violation cannot be counterbalanced by any benefits. If non-negotiable moral requirements can conflict—and Tessman argues that they can—then those situations will be genuine dilemmas and agents facing them will inevitably fail morally. It might seem that if there is more than one moral precept that holds absolutely, then moral dilemmas must be possible. Alan Donagan, however, argues against this. He maintains that moral rules hold absolutely, and apparent exceptions are accounted for because tacit conditions are built in to each moral rule (Donagan 1977, Chapters 3 and 6, especially 92–93). So even if some moral requirements cannot be overridden, the existence of dilemmas may still be an open question.