"PHILOSOPHICALLY SPEAKING...":

Epistemology is the branch of philosophy that deals with knowledge, including the difference between knowledge and justified belief. As students in my "Philosophically Speaking" class discover, part of the problem is one of language: we use the same word, "know," when we say, "I know today is Sunday" and "I know there is milk in the refrigerator." After all, unless you are actually looking at the milk in the refrigerator, there is a non-zero chance that there is *not* milk in the refrigerator, that without you being aware of it someone left the milk sitting on the kitchen counter or drank it all or let a neighbor borrow it or poured it down the drain or myriad other possibilities.

It turns out that the Matses people in Peru embed epistemology in their language. "In Nuevo San Juan, Peru, the Matses people speak with what seems to be great care, making sure that every single piece of information they communicate is true as far as they know at the time of speaking. Each uttered sentence follows a different verb form depending on how you know the information you are imparting, and when you last knew it to be true. For example, if you are asked, 'How many apples do you have?' then a Matses speaker might answer, 'I had four apples last time I checked my fruit basket.' Regardless of how sure the speaker is that they still have four apples, if they can’t see them, then they have no evidence what they are saying is true—for all they know, a thief could have stolen three of the apples, and the information would be incorrect. The language has a huge array of specific terms for information such as facts that have been inferred in the recent and distant past, conjectures about different points in the past, and information that is being recounted as a memory. Linguist David Fleck, at Rice University, wrote his doctoral thesis on the grammar of Matses. He says that what distinguishes Matses from other languages that require speakers to give evidence for what they are saying is that Matses has one set of verb endings for the source of the knowledge and another, separate way of conveying how true, or valid the information is, and how certain they are about it. Interestingly, there is no way of denoting that a piece of information is hearsay, myth, or history. Instead, speakers impart this kind of information as a quote, or else as being information that was inferred within the recent past."
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