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Odd translation of English sentences

In the logic text I'm reading, there is a section on translating English sentence to categorical form, and in it the author describes quantification over times and places. He says words like "always", "never", "sometimes", "whenever", "everywhere, "nowhere" etc in a sentence can be split so that they become both the quantifier and the subject term.

But the examples he gives aren't very convincing. E.g.:

"Joe never says hello"

translates to

"no [times] are [times when Joe says hello]" (E form)

"The sun always shines"

translates to

"all [times] are [times when the sun shines]" (A form)

But the first example, since E propositions are convertible, also says that

"no [times when Joe says hello] are [times]"

But isn't that like saying "no red bricks are bricks"? which is a contradiction.

And for the second, because it follows from "all A is B" that "Some B is A", that

"Some [times when the sun shines] are [times]", which isn't very informative.

I'm starting to believe that the author doesn't know his **** from his elbow.

Re: Odd translation of English sentences

Hi Jeff. Very good ad absurdum analysis on your part! The guy doesn't know what he is talking about.

I would add "Joe never says hello" is a negative singular modal proposition, meaning that Joe is the subject, "says hello" is the predication, does not (say hello) makes that negative, and "ever" is the general temporal modality.
Similarly for "the sun always shines", except that it is positive.

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Re: Odd translation of English sentences

Thanks Avi. Yes I think this is an example of where you have to use a modal proposition. I will have to look at your book on the subject. It's interesting stuff.

Re: Odd translation of English sentences

Jeff: One cannot make a universal proposition out of a singular one, as this guy tries.

What he was trying to do is what I call permutation, i.e. changing a proposition with a common verb into one specifically with the verb "is".

Thus for "Joe never says hello" we would simply say: "Joe (subject) is (copula) not (negative polarity) ever (general temporal modality) 'someone who says hello' (predicate)".

See Future Logic for a fuller treatment of modality and permutation.

With regard to your critique of his universal negative proposition, if you want to get more deeply into this topic, see this essay, on the triviality of the existential import doctrine: http://thelogician.net/7_fortiori/7_appendix_7.htm#_Toc370306065

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