Communities consist of individuals bounds together by social relationships and roles. Within communities, individuals reason about each other's beliefs, knowledge and preferences. Knowledge, belief, preferences and even the social relationships are constantly changing, and yet our ability to keep track of these changes is an important part of what it means to belong to a community. In the past 50 years, our patterns of reasoning about knowledge, beliefs and preferences have been extensively studied by logicians (cf. notably, [12], [19], [1], [6], [10], [18], and [17].), but the way in which we are influenced by social relationships has received little attention. The country and culture in which we are born, our families, friends, partners or work colleagues all play a part in the formation, rejection and modification of our attitudes. One might update one's beliefs about the impact of human activities on climate change after reading a scientific report, become vegetarian after moving to California, decide to change one's appearance because of peer pressure, vote for a candidate one doesn't like personally for the sake of one's department, or argue in a court of law for the innocence of someone one believes to be guilty. From the perspective of individual rationality, such changes are difficult to understand, but they are not arbitrary and are governed by norms that we internalise as readily as the rules of logic. It is the logic of these internalised norms of social behaviour, a social conception of rationality, that we intend to investigate from the standpoint of logic. This paper lays out the problems we wish to address, with a view to promoting the logic of community as an interesting area of research in applied philosophical logic. As a small test case, we will provide some technical details for the first of the following examples. But the main aim of our paper is to describe what we take to be a coherent and fruitful topic for future research, some of which is already under way.
展开▼
