Many of our beliefs in everyday life are rooted in indirect observation, i.e. in the inference from the observed to the unobserved, like our beliefs about upcoming events. But these inferences are problematic. Philosophers have two main questions on them. The first is on their process, and the second is on their justification. The traditional answer to the first question is inductivism. But this approach has some difficulties on answering to the second question that lead some contemporary philosophers to the some new and better answers. Hereupon there are two new general approaches. The first is deductivism and the second is what Gilbert Harman called “the inference to the best explanation” (IBE). In this article I’ll survey inductivism and its difficulties, review deductivism shortly and then I will focus on IBE; firstly I’ll look at Harman’s ideas and finally I’ll try to illustrate van Fraassen’s objections to his claims.
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