[FOM] Disjunction: in or ex?

[Richard Heck]

> Historical: Boole only permitted union of two sets when they are disjoint, so the distinction didn't arise.
>   
My memory---it's been a couple years since my study of Boole---is that
Boole permitted unions only under these conditions BECAUSE he wanted to
interpret "or" as exclusive. Of course, that's not really the right
analogy, the set-theoretic analogue to exclusive "or" being (A \cup B) \
(A \cap B).

Richard

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Richard G Heck, Jr
Professor of Philosophy
Brown University
http://bobjweil.com/heck/
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