The large number of writers who have in recent years attacked the problem of the logical nature of commands appear generally in agreement in accepting the distinction of common grammar between imperative and declarative sentences as representing, albeit in no clear one-to-one manner, some real difference in the logical character of the two types of expression, and possibly in the psychological sign-functioning mechanism itself. The crucial logical difference adduced is that commands can apparently rot be classified as true or false. (...) One is then, however, confronted with the problem of interpreting arguments involving imperatives which appear syllogistic in form, such as:Keep your promises!You promised to pay on Wednesday.Pay on Wednesday! (shrink)

F. P. Ramsey pointed out in Theories that the observational content of a theory expressed partly in non-observational terms is retained in the sentence resulting from existentially generalizing the conjunction of all sentences of the theory with respect to all nonobservational terms. Such terms are thus avoidable in principle, but only at the cost of forming a single "monolithic" sentence. This paper suggests that communication may be thought of as occurring not only by sentence but by clause, a sentential formula (...) closed except for a special kind of variable. Understanding such clauses requires incorporating them within the scope of one's own Ramsey sentence. Many concepts of deductive and inductive logic carry over without great change. But the concepts of truth and designation are extendible to clauses only in the sense that assertions involving them must, to be understood, in turn be construed as clauses and incorporated into the Ramsey sentence. The behavior of these extended concepts of truth and designation suggests an explication of coherence truth within a correspondence-truth framework. (shrink)

This paper argues that if a person's beliefs are idealized as a set of sentences (theoretical, observational, and mixed) then the device of Ramsey sentences provides a treatment, of the mind-brain problem, that has at least four noteworthy characteristics. First, sentences asserting correlations between one's own brain state and one's own "private" experiences are, on such treatment, reconstrued as neither causal, coreferential, nor as meaning postulates, but as clauses in an overall hypothesis (Ramsey sentence) whose only nonlogical constants have "private" (...) meanings. Second, sentences asserting psycho-physical correlations in general, or in other individuals, remain theoretical and susceptible to scientific reduction, though not prejudged to be so. Third, communication between persons having mutually exclusive, "private," observational vocabularies can be made intelligible. Fourth, it becomes possible in principle (though not necessary) that the world could ultimately be given a total description in a scientific language, $L_{\varnothing}$ , without mental primitives. However, such a language would be susceptible to interpretation by a given individual using a metalanguage whose primitives (not among those of $L_{\varnothing}$ ) were privately observational to that individual. His procedure in accomplishing such an interpretation would be to construct a Tarskian truth definition in a metalanguage $ML_{\varnothing}$ and then to incorporate it, by Ramsifying its descriptive terms, in his own overall Ramsey sentence. The physical language, $L_{\varnothing}$ , while not containing a person's primitives, would, of course, be able to define their physical correlates, thus providing a certain sort of mutual mirroring, and a certain sort of relativity. (shrink)