Practical Principles

Eric Dayton's analysis of C. I. Lewis's argument for the validity of the principles of practice in "Pragmatic Contradiction" (Ethics 87 [1977]) is misleading in two ways that do violence to Lewis's theory of practical reason. First, it does not go deep enough and, as a result, mistakes rules we have imposed upon ourselves, the laws of standard logic among them, for rules imposed upon us, either by the world or by the nature of our minds. Dayton fails to appreciate that it is choice and commitment that lie at the heart of Lewis's theory and that, therefore, if the law of contradiction limits the propositional attitudes that can rationally be taken, it is because we have chosen this limit. We must choose some rules, but there are no rules that we must choose. Second, Dayton's analysis rests on what he calls the general principle of consistency for first-person propositional attitudes, (I think) . . .p . .. it is false that (I think) ... not-p ... (1) (p. 229), which is supposed to have a role in Lewis's theory that it does not have. For one thing, it is preferred as the only principle of consistency governing propositional attitudes, whereas Lewis claims that, since attitudes themselves, as well as their objects, may conflict, there is a second principle of consistency ruling out conflict among attitudes. For another thing, (1) characterizes inconsistent attitudes as those whose propositional objects are logically contradictory, whereas Lewis goes the other way around and characterizes logical contradiction in terms of practical (attitudinal) incompatibility. If, indeed, some rules must be chosen, then rules must be followed; else the choice were in vain. To follow a rule is, among other things, to treat the particulars to which the rule applies the same, and to accept a rule is to be prepared to act in the same way toward all the phenomena falling under it. This sameness in the way of acting goes by the name "consistency," not logical consistency, the relation among sentences such that all may be true, but (a more general) practical consistency. To accept a rule, then, is to commit oneself to be practically consistent, that is,