Abstract

It has been widely believed by philosophers and logicians that natural language sentences and arguments have logical forms. Thus, the logical form of an argument is supposed to be responsible for its formal validity. Logical atomists, ideal-language philosophers and natural-language semanticists, among others, all have stressed the importance of logical form. ;Often, views on logical form imply that there is a correct and unique logical form that sentences and arguments have, and that the assignment of a logical form to a sentence or argument is a matter of discovery, a matter about which there is a right or wrong. This view I call "monism". ;I attempt to do two things: one, dissect and explain what a monistic theory of logical form entails; two, argue that monism is incorrect. ;Theories of logical form involve three distinct areas: a natural language whose sentences and arguments are to have logical forms; an artificial language whose expressions are to provide those logical forms; and translation criteria to couple expressions of the one with sentences and arguments of the other. Monism requires that one of two possibilities be true. Either, logical form is inherent in the natural language and can be discerned there, or unique and correct artificial languages and translation criteria can be identified that can then be used to generate unique logical forms for the natural language. ;It turns out that, on the one hand, the constraints provided by the natural languages are too weak, and on the other, that there is too much variability in the choice of artificial language and translation criteria to allow generation of unique logical forms in either case. ;Thus, monism cannot be correct. There is no sense in which a natural language sentence or argument has a unique, correct logical form. For such logical forms to be generated, strong and rich conditions have to be added. Logical form is thus essentially theory-dependent. Even a rich theory such as Davidsonian semantics requires additional constraints before unique logical forms are available. Arguments over the correct logical form of natural language sentences or arguments are thus mostly pointless