Gregory Kavka has recently highlighted, and attempted resolution of, a possible problem with Hobbes's views on state-of-nature co-operation. The problem, having to do with whether it is rational to abide by one's agreements in what appear to be prisoner's dilemma (PD) or PD-like situations, can provisionally be summarized in this way: A covenant of mutual trust is an agreement in which both parties are required to discharge their covenantal obligation, in sequence, at some time after the contract is made (WM,3,14,120–121,124). Hobbes seems to affirm that it is not rational in the state of nature for covenant-parties who have to perform first—first-parties—to keep their agreements, although it is rational for second-parties to do so if first-parties have already performed. These views on the rationality of contract-keeping generate the symmetry enigma: precisely what is the asymmetry between the situations of first-parties and second-parties in the state of nature that makes it irrational for first-parties to do the cooperative thing but rational for second-parties to do so?