This is a comprehensive study of the English word 'or', and the logical operators variously proposed to present its meaning. Although there are indisputably disjunctive uses of or in English, it is a mistake to suppose that logical disjunction represents its core meaning. 'Or' is descended from the Anglo-Saxon word meaning second, a form which survives in such expressions as "every other day." Its disjunctive uses arise through metalinguistic applications of an intermediate adverbial meaning which is conjunctive rather than disjunctive (...) in character. These conjunctive uses have puzzled philosophers and logicians, and have been discussed extensively under such headings as "free choice permission." This study examines the textbook myths that have clouded our understanding of how or and other "logical" vocabulary comes to have something approaching its logical meaning in natural languages. It considers the various historical conceptions of disjunction and its place in logic from the Stoics to the present day. (shrink)

Theorists have oversold the usefulness of predicate logic and generative grammar to the study of language origins. They have searched for models that correspond to semantic properties, such as truth, when what is needed is an empirically testable model of evolution. Such a model is required if we are to explain the origins of linguistic properties by appealing to general properties of linguistic engendering, rather than to the advent of genotypes with the propensity to produce certain brain mechanisms. While the (...) latter sort of explanation has a place, no theory can be considered an `evolutionary' theory without the former. We introduce a general notion of engendering, whose primary virtue is its freedom from assumptions regarding the nature of colloquial change. We use it to frame a conjecture about the evolution of centre embedded clauses; one which makes the fewest possible assumptions about the neural requirements upon individual brains. Keywords: biology of language; epigenesis; engendering; evolution; mutation; population; recursion. (shrink)

Proof and Consequence is a rigorous, elegant introduction to classical first-order natural deductive logic; it provides an accurate and accessible first course in the study of formal systems. The text covers all the topics necessary for learning logic at the beginner and intermediate levels: this includes propositional and quantificational logic (using Suppes-style proofs) and extensive metatheory, as well as over 800 exercises. Proof and Consequence provides exclusive access to the software application Simon, an easily downloadable program designed to facilitate an (...) intuitive understanding of classical logic through the generation and analysis of proofs. It also aids with the representation of natural language sentences in the formal language. Equipped with nearly all the exercises found in the text, Simon helps students work efficiently and effectively by detecting and explaining errors in solutions as they proceed. Students can also submit assignments, view their own records, and check their standing in the class. The complete logic package includes: * The logic textbook, Proof and Consequence *A very helpful study guide to the textbook, containing extra exercises, Simple Simon *Access, through Simon, to the grading software, Simon Says, that allows students to submit assignments and track their grades. (shrink)

Theorists have oversold the usefulness of predicate logic and generative grammar to the study of language origins. They have searched for models that correspond to semantic properties, such as truth, when what is needed is an empirically testable model of evolution. Such a model is required if we are to explain the origins of linguistic properties by appealing to general properties of linguistic engendering, rather than to the advent of genotypes with the propensity to produce certain brain mechanisms. While the (...) latter sort of explanation has a place, no theory can be considered an ‘evolutionary’ theory without the former. We introduce a general notion of engendering, whose primary virtue is its freedom from assumptions regarding the nature of colloquial change. We use it to frame a conjecture about the evolution of centre embedded clauses; one which makes the fewest possible assumptions about the neural requirements upon individual brains. Keywords: biology of language; epigenesis; engendering; evolution; mutation; population; recursion. (shrink)