Talk:Distribution of terms

This article is not clear. Contextual definitions of "term" and "distributed" should be provided or linked to. kostmo 00:48, 10 July 2006 (UTC)

Is case Some A are not B correct?

The article says that B is distributed in Some A are not B. How is this so? It doesn't seem consistent with the definition of distribution. If you simplify things by identifying a term with its extension, you can think of a (binary) categorical clause <quantifier> A <inclusion> B as talking about the three sets

1. A - B
2. A ∩ B
3. B - A,

and it's generally true that A = (A - B) ∪ (A ∩ B) and similarly for B. This should be clear from the Venn diagrams customarily used to depict these relations.

Using this interpretation, the definition seems to say that a term is distributed with respect to a clause when we can equate the term with one of the two subsets (parts) that the clause partitions it into. For example, A is distributed by a clause of the above form when the clause implies A = A - B or A = A ∩ B. Is this indeed what the definition says or means to say?

If so, consider that

• All A are B implies A - B is empty, so A = A ∩ B
• No A are B implies A ∩ B is empty, so A = A - B and B = B - A
• Some A are B implies A ∩ B is nonempty, which doesn't let you equate A or B with either of their parts.
• Some A are not B implies A - B is nonempty, which also doesn't let you equate A or B with either of their parts. In fact, this case tells you absolutely nothing about the parts of B, so I can't see why B is distributed with respect to it.

Honestrosewater (talk) 01:24, 7 December 2010 (UTC)

I've noted, at least, that this is sometimes stated as distribution is granted to subjects in universals and predicates in negatives, and that the relevance of distribution was famously criticized by Geach. "Some A are not B" is a focus of attention in these critiques. —Mrwojo (talk) 17:30, 10 December 2010 (UTC)