Logical Reasoning

PT126 · S1 · Q22 Psychologist: It is well known

A free, expert breakdown of this official LSAT Logical Reasoning question.

Save & drill this skill — build targeted practice sets from questions like this one
Video walkthroughs — watch every question solved step by step
81 official LSATs — as questions, timed sections & full-length tests

Psychologist: It is well known that becoming angry often induces temporary incidents of high blood pressure.

Evidence

It is well known that becoming angry often induces temporary incidents of high blood pressure.

A recent study further showed, however, that people who are easily angered are significantly more likely to have permanently high blood pressure than are people who have more tranquil personalities.

Those with permanently high blood pressure are especially likely to have heart disease.

Conclusion

The recent findings indicate that heart disease can result from psychological factors.

Evaluate

The argument opens with a causal claim: getting mad often causes your blood pressure to get high, but it's temporary. The next two claims express correlations. People who get mad easily are way more likely to always have high blood pressure than more mellow folks. Permanently high blood pressure is correlated with a special likelihood of heard disease. From this, the author drew a causal conclusion: psychological factors can cause heart disease.

Because this is a Weaken question, it's useful to think about what's already wrong with this argument, because the right answer is likely to exploit an existing weakness. Broadly speaking, any time an argument takes correlary evidence and draws a causal conclusion, we should consider two things: could the author have it backwards? Could the thing they think is the effect actually be the cause? Or, could both of the correlated things be effects of some third thing?

So, could heart disease be the cause and psychological factors (being quick to anger) the effect? Sure. Maybe having heart disease causes you to have permanently high blood pressure and having high blood pressure all the time makes it easier to get mad.

Could heart disease and psychological factors (being quick to anger) both be effects of the same cause? Sure. Maybe high blood pressure is the root cause of both heart disease and getting mad easily. Or maybe all 3 of those things are effects of some 4th cause: maybe people are genetically predisposed to all 3 conditions, for example.

Goal

Look for an answer that exploits a classic causal weakness. But, because this is the guantlet (the hardest stretch of LR questions from 15-23), if you don't find your prediction, try each answer on for size with an open mind.

22.

Which one of the following would, if true, most weaken the psychologist's argument?

Those who are easily angered
Out of Scope
Recovery from episodes of heart disease is not relevant to the argument about developing heart disease.
0% picked this
Medication designed to control high
Unclear Impact
This could be a tempting keep because it seems to suggest that perhaps one of the causal relationships the argument hinges on (being quick to anger causing high blood pressure) is actually reversed. The problem is, in this answer, the blood pressure being controlled is not necessarily permanently high. Furthermore, affecting one’s mood does not necessarily imply that one is easily angered. Without that specificity, the impact of this answer is unclear.
20% picked this
People with permanently high blood
Strengthens, if anything
If anything, this answer is kind of a control group: a classical causal strengthener that shows a correlation between the absence of the proposed cause and the absence of the purported effect. If people who have more tranquil personalities (and are thus not quick to anger) almost never develop heart disease, that shows that the absence of the cause (quick to anger) is correlated with the absence of the effect (heart disease).
11% picked this
Those who discover that they
Term Shift
This could be tempting on a first pass because it seems to suggest an alternative explanation of the correlation between anger and heart disease. It's not that being angry causes heart disease, it's that knowing you have heart disease makes you angry! The problem is, becoming more easily frustrated by small difficulties is not the same as being easily angered. Furthermore, becoming more easily frustrated is a relative change, while being easily angered is a fixed state of being.
19% picked this
Correct
The physiological factors that cause
Why this is right
This answer establishes a cause and effect relationship: whatever it is that's going on in our bodies that causes permanently high blood pressure also causes people to be quick to anger. In some ways, this is a pretty classic "3rd thing causes both correlated things" answer. But it's got some quirks, too. For one thing, it doesn't ever mention heart disease, and that's the effect in our conclusion. But, our argument does seem to hinge on a 3 step causal chain: quick to anger causes permanently high blood pressure, and permanently high blood pressure causes heart disease. This answer choice attacks the first link in that causal chain by alleging there is a third cause (physiological factors) that explains the first two correlated things: high blood pressure and being quick to anger. Even though it doesn't attack the second link in the chain, attacking the first link is enough to do some damage, so this will be the best available answer.
Skill tested: Weaken · how this choice captures the argument's function is the move to repeat next time.
50% picked this

Continue the review in LSAT Lab

Save this question, watch the video walkthrough, and drill similar questions in your LSAT Lab account.

Save and practice this skill

LSAT Lab

Turn this review into a targeted study plan.

Save this question, drill more like it, watch the video walkthrough, and track your progress in your LSAT Lab account.

Start practicing free