Theories of Rationality and Principles of Charity

While there is no consensus over how the "principle of charity" should be formulated, there is nevertheless a general agreement that the use of that principle is required in attributions of rationality. What has perhaps not been generally noted is that taking the principle of charity seriously results in a conception of rationality that is at odds with the conception underlying many discussions concerning rationality, especially in the philosophy of science. What I would like to do here is articulate this conception. My purpose is not to produce a refutation of the standard conception. Rather, it is to challenge the thought that unless the standard conception is correct, the result is skepticism. By challenging this thought, the way is open for some non-skeptical doubts. A theory of scientific rationality falls into two parts, depending upon whether we are dealing with the rationality of scientific actions or of scientific beliefs. One part is concerned with the various activities characteristic of science-choosing research projects, designing and conducting experiments, etc. An account of rationality here consists in providing a framework for identifying a goal or aim-sometimes gravely referred to as "the aim of science"--and showing that there is an appropriate connection between the activity in question and the goal. The other part is concerned with scientific theories. An account of rationality here consists in providing a framework for judging whether the reasons for believing these theories are good reasons.' Although I will confine myself to this part of a theory of rationality, I hope it will be clear how the following remarks are to be modified to apply to the other part. The traditional approach to articulating a theory of rationality proceeds by formulating criteria or rules specifying the conditions under which one thing is a good reason for believing something else. The standard work in confirmation theory takes its problem to be that of explicating the conditions