 On the master rule approach, the task of the natural law theorist is to identify some master rule which bears on the basic goods and, perhaps in conjunction with further factual premises, is able to produce a stock of general rules about what sorts of responses to the basic goods are or are not reasonable. While it is far from clear whether there was a single way that Aquinas proceeded in establishing moral norms from the primary precepts of the natural law in the Summa Theologiae, John Finnis has argued (Finnis 1998, p. 126) that Aquinas employed this master rule approach: on his view, Aquinas held that this master rule is the rule of universal love, that one should love one’s neighbor as oneself. This rule bids us to respond to the good lovingly wherever it can be realized, and from it we can see that certain ways of responding to the good are ruled out as essentially unloving. Grisez clearly employs this approach: he writes that the first principle of morality is that “In voluntarily acting for human goods and avoiding what is opposed to them, one ought to choose and otherwise will those and only those possibilities whose willing is compatible with a will toward integral human fulfillment” (Grisez 1983, p. 184). This first principle, Grisez says, contains implicitly within it various “modes of responsibility” from which particular moral rules can be derived.