I'm fairly sure that this is just an unnecessary way of wording a relatively simple conditional, but its kind of tripping me up. I feel like most conditionals like this are worded to be exclusive (If A then either B or C but not both), but this seems to be inclusive (could be either one or both). Am I correct to assume that having W tells me I'll have either F, T, or both, but NOT having either of F or T means I can't have W. Just bit confused by this wording that I really haven't seen outside the fruit stand game.
"If the stand carries watermelons, then it carries figs or tangerines or both."
W-->F or T or FT
~F-->~W
~T-->~W
I guess the big clarification I need is whether a conditional with "or" is inclusive or exclusive, assuming its not noted somehow ("but not both").
Strange wording of an "or/and" conditional (fruit stand gam) Forum
- Easy-E

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- Joined: Fri Feb 18, 2011 1:46 pm
- KevinP

- Posts: 1322
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Re: Strange wording of an "or/and" conditional (fruit stand gam)
If not indicated otherwise, or is always inclusive. In this case, the "or both" is completely extraneous; the statement could have very well just said "If the stand carries watermelons, then it carries figs or tangerines." You are incorrect to assume that if you don't have either F or T, then you don't have W. However, if you have neither F nor T, then you don't have W.emarxnj wrote:I'm fairly sure that this is just an unnecessary way of wording a relatively simple conditional, but its kind of tripping me up. I feel like most conditionals like this are worded to be exclusive (If A then either B or C but not both), but this seems to be inclusive (could be either one or both). Am I correct to assume that having W tells me I'll have either F, T, or both, but NOT having either of F or T means I can't have W. Just bit confused by this wording that I really haven't seen outside the fruit stand game.
"If the stand carries watermelons, then it carries figs or tangerines or both."
W-->F or T or FT
~F-->~W
~T-->~W
I guess the big clarification I need is whether a conditional with "or" is inclusive or exclusive, assuming its not noted somehow ("but not both").
Here's a diagram:
W -> F OR T
~(F OR T) -> ~W (contrapositive)
~F AND ~T -> ~W (De Morgan's law)
Hope this helps.
- Easy-E

- Posts: 6487
- Joined: Fri Feb 18, 2011 1:46 pm
Re: Strange wording of an "or/and" conditional (fruit stand gam)
KevinP wrote:If not indicated otherwise, or is always inclusive. In this case, the "or both" is completely extraneous; the statement could have very well just said "If the stand carries watermelons, then it carries figs or tangerines." You are incorrect to assume that if you don't have either F or T, then you don't have W. However, if you have neither F nor T, then you don't have W.emarxnj wrote:I'm fairly sure that this is just an unnecessary way of wording a relatively simple conditional, but its kind of tripping me up. I feel like most conditionals like this are worded to be exclusive (If A then either B or C but not both), but this seems to be inclusive (could be either one or both). Am I correct to assume that having W tells me I'll have either F, T, or both, but NOT having either of F or T means I can't have W. Just bit confused by this wording that I really haven't seen outside the fruit stand game.
"If the stand carries watermelons, then it carries figs or tangerines or both."
W-->F or T or FT
~F-->~W
~T-->~W
I guess the big clarification I need is whether a conditional with "or" is inclusive or exclusive, assuming its not noted somehow ("but not both").
Here's a diagram:
W -> F OR T
~(F OR T) -> ~W (contrapositive)
~F AND ~T -> ~W (De Morgan's law)
Hope this helps.