Roger Bacon on Equivocation

Abstract

Many of the things in the world differ from one another to a substantial degree and yet we find ourselves often using one and the same word to refer to these objects. The result is sometimes confusing to those in attendance, especially when the truth value of expression is affected. just saw the dog a moment ago is a less than helpful response from a backyard astronomer having just looked at the dog-star when his neighbor has inquired about his own canine pet. And since the truth value of propositions plays a substantial role in the construction of sound deductive arguments, it is no wonder that Aristotle treated equivocation as one of the causes of deception that constitute argument a fallacy.1 Interestingly, however, while Anselm made a great contribution in developing a theory of paronomy2 and 12th and 13th century logicians advanced the philosophy of language through their theories of the properties of terms, the theory of equivocation laid down by Aristotle was not altered in any significant way throughout the Middle Ages and, with one exception, his triple division of species of equivocation was tampered with only with great reserve. The exception was Roger Bacon who, having given a traditional expose once in 1252, returned to the question in 1267 and 1292 with a freshness which led to, in the words of Jan Pinborg, an original systematization of possible changes [in signification] or equivocations, which has no medieval parallels.3 In this article I propose (Section I) to give a brief overview