Logical reasoning PrepTest 158 · Section 3 · Question 25

We don't have any principle that leads to the conclusion "Government NOT justified in interfering," so we cannot choose an answer that draws this conclusion. We only have NOT justified as a sufficient condition, not as a necessary one.

This argument at least leads to a conclusion our principle could justify — the government justified in interfering — but both halves of the sufficient condition are missing. The lawn isn't causing physical harm, and we don't know if the neighbor overgrows his lawn to help others, so this one is incorrect.

Not wearing a helmet is "increasing the likelihood of physical harm," but not "to others," so it doesn't meet the first half of our sufficient condition. And the other half is absent as well. We don't know if motorcyclists decline helmets to help others (or — unless they really want to help trauma surgeons practice their craft — how this could feasibly help others).

Here we have a situation in which it's true that the corporation was "not motivated by the intent to help others," but it's missing the condition "increases the chance of physical harm to others." The company may be making ineffective drugs, but that doesn't automatically mean they're harmful.

Argument or Facts:
Facts

Question Type:
Principle (Must Be True)

Stimulus Summary:
If an action would increase the chance of physical harm to others, and that action is not motivated by a desire to help others, the government is justified in interfering.

Strategy Overview:

1. Argument or facts? Always a set of facts (one or more principles)
2. Diagram the principle
3. Select the answer choice that correctly applies principle
   1. Either through positive argument structure (Passage: "S → N." AC: "S, therefore N") or contrapositive argument structure (Passage: "S → N." AC: "NOT N, therefore NOT S")

Answer Anticipation:
This is the Must Be True variety of a Principle question (because the principle is in the passage, not answer choices). Those are almost always diagrammable, this being no exception. So, we diagram:

1. Action Increases Chance of Physical Harm to Others AND NOT Action Motivated by Desire to Help Others → Government Justified in Interfering

And the contrapositive:

NOT Government Justified in Interfering → NOT Action Increases Chance of Physical Harm to Others OR Action Motivated by Desire to Help Others

Be careful not to commit a reverse-without-negating flaw here; we don't know that the government isn't justified in interfering in actions motivated by the desire to help others, for example. That could be true or could be false. All we know is that if these specific two conditions are met, interference is justified; and if interference was not justified, one of the two conditions must not have been met.

Answer Choice Explanation:
Finally! A situation in which there is an increased chance of physical harm to others (people getting hurt in a riot) and not a desire to help others (making the speech to further her own political ambitions). Both halves of the sufficient condition are present; therefore the conclusion that interference is permissible is fully justified, and (E) is correct.

Key Takeaway:
Many Principle (Must Be True) questions feature compound sufficient conditions. So make sure to track whether both sufficient conditions need to be present (i.e., it's an "and" sufficient condition) or if just one needs to be present (i.e., it's an "or" sufficient condition).