I am passionate about the issue of Linguistic Communication (aka testimony) (you can see here my italian blog about it). Many authors tend to think that Liguistic Communication should not be admitted among the instruments of knowledge. But this leads to terrible consequences, since without it our everyday life would just turn out to be impossible. How could we systematically doubt whatever we are told? We know by being told even the most important things in our lives, such as our name and date of birth.
Hence, I tend to favour the Indian shcools such as Nyāya and Mīmāṃsā, which admit śabda (linguistic communication) among the means of knowledge (pramāṇas). I am also always interested in reading Western accounts about it. Recentlty, I read the ppt of a talk by Stephen Wright discussing gullability and rational behaviour. Stephen summarises the arguments by Burge about the fact that people are rational beings and that, hence, they lie if they have good reasons to do it and tell the truth if they have good reasons to do it. What happens if they have no good reasons for doing either? All else being equal, they would tell the truth. In fact, telling the truth is better for your reputation and it is better because next time people are more likely to believe you, even if you are lying. Hence, even if you are ready to become a liar, it is convenient for you not to lie whenever you have no good reasons for doing it.
I am happy with the conclusions of this argument (we are entitled to believe what people say as our default attitude), but I am not totally persuaded by its bases. If the entitlement is based on the theory that people behave rationally, then how to face the fact that stupidity is by definition more common than one could imagine and that, hence, there are many many people who behave in a non-rational way. How to answer this objection?