 While McKinsey’s formulation of (LO) is rather complicated, the basic idea is quite simple. According to (LO), an agent S’s primary obligation is identical to the obligation that possibilists believe S has. Additionally, for every maximal act-set M (or a life) that, at t, S can perform, if M is not identical to the best maximal act-set that, at t, S can perform, but is better than the maximal act-set that S will in fact perform, then at t S has a moral obligation to perform M. To illustrate, consider this case: