Unfortunately for this idea, native speakers do not always follow the rules of formal logic when they speak; sometimes, perfectly acceptable utterances defy logic.
Unfortunately for this idea, native speakers do not always follow the rules of formal logic when they speak; sometimes, perfectly acceptable utterances defy logic.
An indirect condition occurs when there is a logical gap in the overt meaning between the two parts of a conditional sentence. For example, the stated outcome in the following does not depend on the fulfilment of the if-clause;
You look tired, if you don't mind my saying so
If you're going in July, it will not be raining
[FONT="]Chalker, Sylvia and Weiner, Edmund(1993.83-4) The Oxford Dictionary of English Grammar, 2nd edn, Oxford: OUP[/FONT]
An important issue here (not the only one) is the use of parentheses. We do not use parentheses in natural languages the way we do in formal languages. We have an example in this thread.
not a or b
Is it
(not a) or b
or
not (a or b)
?
You chose one interpretation, which was different from mine. Both are equally valid because English has no means of distinguishing between them without changing the wording.