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Episode 47: Alexandru Baltag discusses the logic of knowledge

In our latest episode, we talk some epistemology with Alexandru Baltag, Associate Professor of Logic at the Institute for Logic, Language, and Computation in Amsterdam.  Click here to listen to our conversation.

Alexandru BaltagKnowledge may seem straightforward at first.  But try to give an exact definition of what it is, and you’ll soon find that it’s more difficult than you would have thought.  Maybe it’s just belief.  No, wait–if I believe something false, that probably can’t count as knowledge.  Maybe it’s true belief.  But I may believe something for the wrong reason, or for no reason at all.  So maybe it’s true belief that’s supported by good evidence.  Oh, my; it seems there are famous counterexamples to that definition as well.

In order to accommodate a seemingly endless array of counterexamples, philosophers have been pushed into advancing ever more sophisticated and unusual definitions.  For instance, some have proposed that I know such-and-such to be true just in case no further influx of true information about other things could make me change my mind about it.  Some have proposed that I know such-and-such to be true just in case someone telling me about it would be redundant.  And some have proposed a link between knowing things and alternate possible situations.  On that view–called the counterfactual theory of knowledge–I know something just in case if the world were a bit different, and the fact in question were true, I would believe it, and if the world were a bit different and the fact in question were false, I wouldn’t believe it.

The moral that Baltag would have us draw from these many definitions of knowledge isn’t so much that one of them is correct and the rest get things wrong–rather, it’s that each definition endows knowledge with distinct mathematical properties, which you can prove things about.  And exploring these mathematical characteristics can help us understand the many forms that knowledge takes.  For instance, you can prove that it follows from some of these definitions that if I know something, then no further information I may learn can get me to change my mind.  You can also prove that according to other definitions, this isn’t the case–which means that they represent knowledge as something defeasible.

Alexandru Baltag argues that studying the mathematical properties of these different conceptions can help us rethink how to manage the information we receive more responsibly, particularly when it comes to information we receive from sources like the world wide web.  Tune in to hear his suggestions!

Matt Teichman

Posted in Podcast.


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