Conclusion: Sylvia's "dinner party is certain to be a success."
Why? Because "congenial guests and a plentiful supply of good things to eat and drink will ensure a successful dinner party." We know that "Sylvia has prepared more than enough to eat and drink and her guests are all congenial people."
Let's diagram the argument.
"Congenial guests and a plentiful supply of good things to eat and drink will ensure a successful dinner party."
PR: CG and PSGTED ==> SDP not SDP ==> not CG or not PSGTED
"Since Sylvia has prepared more than enough to eat and drink and her guests are all congenial people,"
P: CG and PSED
"her dinner party is certain to be a success.
C: SDP
The sufficient conditions of the principle rule are having "congenial guests and "a plentiful supply of good things to eat and drink. If you have both these things, then we can conclude that you will have a successful dinner party.
We know that Sylvia has "congenial guests, but we only know that "she has prepared more than enough to eat and drink. We do not know whether the things she has prepared are "good things, which is a part of the sufficient condition "a plentiful supply of good things to eat and drink. What if Sylvia has prepared more than enough bland food to eat and drink? This would not satisfy the sufficient condition.
Thus, the sufficient condition of the principle rule has not been invoked.
Answer choice (D) states: "If soup is made with a well-seasoned meat stock and fresh ingredients, it will always be welcome at dinner. Since to his meat stock Arnold added only fresh ingredients, the resulting soup is certain to be welcome at dinner.
Conclusion: Arnold's "resulting soup is certain to be welcome at dinner.
Why? "If soup is made with a well-seasoned meat stock and fresh ingredients, it will always be welcome at dinner. We know that Arnold has "Added only fresh ingredients to his meat stock.
Let's diagram.
"If soup is made with a well-seasoned meat stock and fresh ingredients, it will always be welcome at dinner.
PR: WSMS and FI ==> W@D not W@D ==> not WSMS or not FI
"Since to his meat stock Arnold added only fresh ingredients,
P: MS and FI
"it will always be welcome at dinner.
C: W@D
The sufficient conditions of the principle rule are the soup being made with "a well-seasoned meat stock and "fresh ingredients. If we have both of these, then you can conclude that the soup "will always be welcome at dinner."
We know that Arnold has fresh ingredients, but we do not know whether his meat stock is well-seasoned. We merely know that Arnold has used meat-stock. So, just like in the stimulus, the sufficient condition of the principle rule has not been invoked.
Hope that was helpful! Please let us know if you have any other questions.
jamesioMay 8, 2018
it amazes me how tricky the test makers try to be. i almost made the vital mistake of confusing "sylvia has prepared more than enough to eat & drink" as "plentiful supply of GOOD things", marked answer choice "C" then moved on.
just goes to show how attentive you need to be when reading the stimulus.
excellent explanation again! superb
MalenJanuary 2, 2021
doesn't "will ensure" mean it would be necessary? I interpreted that as if you want a successful party you need congenial guests and a plentiful supply of good things to eat and drink.
