Inference Question in regards to coinciding of events

[timmydoeslsat]

I suppose I am of the personality type where I must know the answer to everything. At least to questions that I know an answer has been established.

I would like clarification on this issue.

If i were to state that: the lower one's blood pressure is, the lower one's risk of heart attack...

Does that give me the ability to infer that the higher one's blood pressure is, the higher one's risk of heart attack.

I have heard differing opinions on this matter from respected posters, such as mlbrandow who frequents this board.

I am unsure what to make of this matter.

[minhtientm249]

I've always wondered the same thing. But I think there're different answers to this question simply because with different assumptions, you might have different answers.

If you assume that the larger the difference between a certain "normal" level of blood pressure, the risk is lower then you can't conclude that higher the blood pressure associates with higher risk.

If you assume that the blood pressure and the risk correlate along a certain "measurements", your conclusion is correct.

If you assume that anything lower than a point of blood pressures results in the lower of the risk, but no such correlation in any measurement higher than that point, then you can't conclude the higher the blood pressure, the higher the risk.

It could be anything. So I think that for these questions, this statement alone is not enough to conclude what you've asked. Probably there will be additional premises or information in the stimulus or answer choices.

Hope that helps.

[ManhattanPrepLSAT1]

I would like clarification on this issue.

If i were to state that: the lower one's blood pressure is, the lower one's risk of heart attack...

Does that give me the ability to infer that the higher one's blood pressure is, the higher one's risk of heart attack.

Great question Timmy and the answer is yes. The reason why you've probably encountered conflicting ideas on this is because there are some common flawed arguments that play on this idea.

Here's a valid argument:
The lower one's blood pressure, the lower one's risk of heart attack. Jimmy has lower blood pressure than George. Thus, George has a higher risk of heart attack than Jimmy.

Here's an invalid argument:
The lower one's blood pressure, the lower one's risk of heart attack. Jimmy has low blood pressure. Therefore, Jimmy has a low risk of heart attack.

The issue on the second (flawed) example is that the argument moves from a relative claim to one that's absolute. Similar to me saying that since pizza is healthier than chocolate cake, pizza must be healthy.

Let me know though if you have another twist to this example that's still unclear!