Monday, February 23, 2015

Blanket Statement

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(C)Copyright 2015, C. Burke.

Blanket statements are always wrong. Think about it.

I'm having a flashback to logic lessons where we took apart statements like "All the classrooms are too cold." and had to negate it properly. First thing, the opposite of "All" in NOT "None" (any more than "too cold" could be changed to "too warm"). The opposite of "All" is "Not All". Or "Some" (which could mean one because it would only take one room to disprove the statement). And then there was the ever-popular "There Exists a Room Such That ..."





2 comments:

Anonymous said...

If this claim about blanket statements is true, then it's false. Oops: reject that possibility as contradictory.
On the other hand, if it's false, then some blanket statements are true (not false). In fact, there are lots of them: any universal statement representing a true subclass inclusion, like "all squares are quadrilaterals."

(x, why?) said...

So you're saying my blanket statement was wrong.