John Hare’s God’s Command, Chapter 4, “Can We Deduce Morality from Human Nature?” Introduction & Section 4.1.1: The Non-Deducibility of the Law from our Nature:

Introduction: Hare has been arguing that eudaemonism (in the four forms discussed) does not have a proper place for what Scotus calls, following Anselm, the affection for justice. The present chapter is about a different dividing question in moral theory: can morality be deduced from “natural” facts, or from statements about the “natural” properties possessed by people and actions? The term “natural” here is problematic. The first section of the chapter discusses Scotus’s view that the moral law can’t be deduced from human nature, but is exceedingly fitting to it. In the second and fourth sections the denial of deducibility from “natural facts” will extend to a dispute with contemporary theorists. The third section examines RMH’s take on natural facts. The second section looks at Adams’ attempt to deduce a way to fix the reference of “good” from facts about what most humans most of the time think is good. Hare calls this “consensus deductivism.” The fourth section looks at the attempt by Foot and Hursthouse to deduce conclusions about moral goodness from facts about the characteristic human form of life. Hare calls this “form-of-life deductivism.” No entirely neat separation between these two kinds of view is possible.

4.1 SCOTUS.

4.1.1: The Non-Deducibility of the Law from our Nature

Scotus rightly denies that the moral law can be deduced from human nature. Note, first, it is deducibility that is denied, rather than some weaker relation such as fittingness. Scotus accepts that the moral law, such as the second table of the Ten Commandments, fits human nature exceedingly well, but he insists nonetheless that this is natural law only in an extended sense, not in the strict sense, because God is free to command creatures with human nature otherwise. Natural law in the strict sense is “known from its terms” or deducible from what is known in this way.

Second, it is moral law that is denied to be deducible from human nature, and not goodness. His examples of moral law are from the second table of the Ten Commandments, though we should not assume that he intends this list to be exhaustive. Third, the term from which deducibility is denied is human nature. But this has to be understood in a way that is not already conceptually subsumed under moral law. If we define “human being” as “a being under moral law,” or if we make being under moral law essential to the kind “human being” (as Kant does), then there will be a trivial deduction from the premise that a being is human to the conclusion that it’s under the moral law. On the other hand, if we deny that humans are by nature under the moral law, then we have simply denied deductivism from the beginning and begged the question.

Here’s a third alternative. We can grant that human beings are by nature such that they are fulfilled, or they reach their end, by loving God. Scotus says our end is to be condiligentes, co-lovers, which is to say that we enter into the love that is between the three persons of the Trinity. This human love of God, however, is distinct from the way angels love God or God loves Godself; humans love God as rational animals. We can ask whether we can deduce the moral law from our end specified as being condiligentes.

One prominent case Scotus gives is the commandment “You shall not steal.” Private property, he points out, is presupposed by the commandment but is not essential to human beings. There is no deduction of the proscription of theft just from human nature, and the divine command is to that extent contingent; there is no necessity here binding the divine will.

But stealing is not the most difficult case for someone who wants to maintain the contingency of the second table. What about killing? God could bring a killed person back to life, but perhaps more needs to be said. The question of whether the command not to kill is contingent tout court is not settled by the question of whether God could command otherwise given merely human nature. We can ask, “Could God command the killing of the innocent if not just human nature, but our circumstances stayed the same; in particular, if we stayed dead once killed?” In a later section Hare will take this up.