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rzach / forallx-yyc

UCalgary version of forallx, an introduction to formal logic
https://forallx.openlogicproject.org/
Creative Commons Attribution 4.0 International
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Should the section 3.1 on Joint Possibility clarify something about validity of arguments? #67

Closed kedarmhaswade closed 1 year ago

kedarmhaswade commented 1 year ago

This observation pertains to content clarification and it could be subjective. Filing it as an issue according to the emerging guidance from #65.

I am studying from revision 79af9e0.

§3.1 is on Joint Possibility. It refers to whether given "sentences" are jointly possible.

It seems to me that if given sentences are premises of an argument, it can only be valid if the premises are jointly possible.

Should §3.1 end with a comment reflecting the above, or is it too obvious?

rzach commented 1 year ago

If the premises are not jointly possible, the argument is actually automatically valid. But you're right that could be clarified.

kedarmhaswade commented 1 year ago

Oh, right! A collectively false statement can imply anything.