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- Joined: Jan 10, 2018
Jon Denning wrote:
For your next question concerning rule #4 (a trickier rule, in my opinion), we once again have a two-part statement: if either L or O is not in the park, then F and S are both in. The "not L" or "not O" sufficient conditions would allow us to represent this with two diagrams:
(1) L F and S ; contra: F or S L
(2) O F and S ; contra: F or S O
Do you see how these would also cover the condition where both L and O are not in? In that case it would still be clear that F and S were in the park. Just remember that multiple conditions with "or" or with "and" require that you change between the two as you take contrapositives. So "or" becomes "and" and the terms get negated, and vice versa.
I would be very grateful for a clarification on this! How does this rule apply to the case where both L and O are not in? So 'not the case that the park contains both laurels and oaks' means Not (L and O) which means Not L or Not O? Wouldn't this be the only possibility then?
Can I know how the language used in the fourth rule 'not the case that the park contains both laurels and oaks' differs from that in the third rule 'either laurels or oaks, but not both' ?
Either L or O (Possibilities include L, O, or both L and O)
Either L or O, but not both (Possibilities include L or O)
Not Both L and O (Possibilities include L or O, or none)