Justification and Probability

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Under what conditions are we justified in believing something? A very simple and natural answer to this question is that we are justified in believing something when it is sufficiently likely to be true. Managing one's beleiefs in a reasonable and responsible manner is all about minimising the risk of error. As simple and natural as this answer seems, however, I believe it to be mistaken.Suppose that 100 people attended a concert but we know that only one ticket was ever sold. As such, we know that only one of the people at the concert attended legitimately and the other 99 were gatecrashers. Suppose we know that Joe was one of the people who attended the concert but have no further information about him. Clearly, in light of our evidence, it's very likely that Joe was a gatecrasher. But should I really draw the conclusion that Joe was a gatecrasher and treat him accordingly? Should I go about asserting that Joe was a gatecrasher - should I inform his friends, his family, his employer for instance? Should Joe be arrested and convicted and appropriate punishment applied to him? Most of us would agree that this would be exceedingly unfair and, under prevailing legal practice, statistical evidence of this kind would not be deemed a legitimate basis for a conviction.But if I'm not justified in believing that Joe was a gatecrasher, then justification is not simply a matter of likelihood after all - there must be more to it than this. Interestingly, if an eye-witness claimed that she saw Joe scaling the fence to get into the concert then we would generally have no qualms about believing that Joe was a gatecrasher and acting accordingly - and such evidence could well be deemed a legitimate basis for conviction in a court. And yet, we're all aware that testimony is fallible - the eye-witness could be lying or mistaken. Indeed the probability that Joe was a gatecrasher given that a witness testified that she saw him scaling a fence is plausibly not as high as 99%. My primary aim in this project is to try and get to the bottom of this puzzle and, in so doing, come to a new understanding of what it takes to be justified in believing something. The research is relevant not just to epistemologists and academic philosophers but to anyone who has wondered what to believe about a given topic or how to evaluate a given piece of evidence. As the above example suggests, the research also has a bearing on questions about how best to understand and rationalise our legal practices. I aim to publish the results of this research in a monograph and a research paper. The research will be conducted primarily in Scotland and in collaboration with a number of philosophers working throughout Scotland. Scotland, at present, boasts a number of high profile philosophy departments and research centres with particular strength in epistemology.