Self-study
Support Rhonda will see the movie tomorrow afternoon only if Paul goes to the concert in the afternoon. ████ ████ ███ ██ ██ ███ ███████ ██████ ███ ██████ ██ ██ ██ ███ ████████ ████████ ███ ███████ ██ ██ ██ ███ ████████ ██ ██████ ████ ███ ███ ███ █████ ████████ ██████████
Method of Reasoning
The stimulus can be diagrammed as follows:
15.
The pattern of reasoning displayed █████ ██ ████ ███████ ██████████ ██ █████ ███ ██ ███ ██████████
a
If Janice comes ██ ██████ ████ ████ ███ ███ ███ █████ █████████ ██████ ████ ███ ████ ██ █████ ██████ ███ ███████ █ ███████████ ████████ ██████ ███ ███████ █ ███████████ ██ ███ ████ █████ █████
Mismatched premises. The stimulus outlines a conditional chain of A→B→C then negates the final necessary condition. (A) gives a sufficient condition (Janice coming to visit) and two necessary conditions (Mary not paying bills and Janice locating baby sitter). This does not parallel the conditional chain of A→B→C from the stimulus.
b
Gary will do ███ ███████ ████████ ████ ██ █████ ███ ██ ██ ██ █████ ██████ █████ ██ ████ █████ ████ ███ ████ ██ ██ ██ █████ █████ █████ ██ ███ ████ ████ ████ ███ ██ ███ ███████ █████████
The diagram for (B) parallels the diagram of the stimulus:
c
Kelly will barbecue ████ ███████ ██ ██ ████ ███ ████ ███ ███ ██████ ███ █████ ██████ ████████ ███ ████████ ████ ███ ████ ███ █████ ███ ██████ ████ ███ ████ █████ ██████ ██ █████ ████ ███ ████████ ████ ████████
Mismatched premises. The stimulus outlines a conditional chain of A→B→C then negates the final necessary condition. (C) gives two sufficient conditions (/rain and fresh trout) for a necessary condition (barbecuing fish) then fails one of the sufficient conditions (/fresh trout).
d
Lisa will attend ███ ██████ ███████ ████ ████ ████ ██ ███ ██ ███ █████████ █████ ██ █████ ████ ████████ ████ ████ ███ ██████ ███ ████████ ███ █████ █████ ██ ████ ████ ██████ ███ ████████
Mismatched premises. The stimulus outlines a conditional chain of A→B→C; (D) gives a sufficient condition (Lisa attending) and a necessary condition (Jared OR Karl attends) and confirms one of the necessary conditions (Jared will attend).
e
George will not ██ ██ ███ ██████ ████████ ██████ ████ ██████ ██ ███ ████ ████ ██ ██ ███ ██████ ████ ██ ██ ███ ████████ ████ ██ ███ █████████████ ████ ███ █████████ ████ ██ ███ █████████████ ██ ██ ████ ██ ██ ███ ███████
Mismatched premises. The stimulus outlines a conditional chain of A→B→C; (E) gives also gives a conditional chain (George goes→Mark goes→ Mark can postpone most appointments). However, the stimulus then negates the final necessary condition, but (E) does not do this. (E) only says that Mark has postponed “some” appointments.