Jeremy on May 8, 2019
I was able to eliminate A, C, and D. When choosing between B and E, I decided on E on the basis of the construction "But since no one can investigate what does not happen [...]." This seemed much more closely parallel to the passage's claim that "The successful spy is never caught" in contrast to B's "But unconscious motives are usually impossible to acknowledge."
In reviewing, I attempted to diagram the passage as well as these two answer choices out:
P: SC --> SF (NOT SF --> NOT SC)
P: RM --> SC (NOT SC --> NOT RM)
C: NOT SF --> NOT RM
Answer choice E:
P: IC --> ED (NOT ED --> NOT IC)
P: NOT IC --> NOT I (I --> IC)
C: NOT IC --> NOT ED
This answer choice can be eliminated: "Don't just reverse."
But how can we diagram B? I got this far:
P: AM --> ACM (NOT ACM --> NOT AM)
P: UM --> (usually) NOT ACM
Please help - thanks!
Ravi on May 10, 2019
Jeremy on May 11, 2019