Convenções, conhecimento comum e convenções alternativas

Abstract

In this paper I’ll try to answer the question about whether the common knowledge condition, which according to David Lewis defines a convention, is really necessary to explain the social phenomenon thus designated, and also whether Lewis’ definition accords with our common intuitions about this notion. In order to achieve my goal I’ll test the definition by asking two questions: Can the definition explain the origin of conventions? And can it explain the way conventions maintain themselves in use over time? In 1. I’ll present the notions of common knowledge and salience, and I’ll try to show how both are strictly connected in a way that one cannot be conceived without the other. In 2., following the literature on game theory developed after and over Lewis’ definition, I’ll introduce Ken Binmore’s criticisms about whether it is possible for an event to become common knowledge in a large population. In 3. I’ll introduce some examples by Tyler Burge which question the need to include, in the definition of convention, the proviso according to which there has to be common knowledge of alternative conventions. In 4. I’ll evaluate the arguments presented and conclude that a weakened version of the proviso is necessary to give a complete answer to the relevant questions.
Key-words: convention, salience, common knowledge, truism, social function.