QUESTION TEXT: Humankind would not have survived, as it…
QUESTION TYPE: Parallel Reasoning
CONCLUSION: Humanity’s ancestors were at least somewhat altruistic.
REASONING: Humanity survived because early humans were ready to sacrifice themselves to protect their kids and relatives. This sacrifice can be viewed as altruism. And humanity has survived.
ANALYSIS: This is a good argument. It has the following structure.
- Humans survive ➞ ready to sacrifice ➞ form of altruism.
- Humanity did survive. So early humans had a form of altruism.
I’ll admit that I didn’t have this exact structure until after I looked at the argument. But I had a rough idea and the right answer stood out for me. I’m presenting the exact structure so you can learn from it – but know that you don’t need to have a precise understanding to see that the other answers are missing something.
One important element in the stimulus: “as it clearly has [survived]”. This isn’t a conditional statement. Instead, it’s a statement of fact showing that a condition occurred. It’s like saying “cats have tails. And this animal is a cat”. The second statement is a fact that lets us draw the conclusion “this animal must have a tail”.
It turns out that all of the wrong answers are bad arguments! That’s another way to eliminate them, apart from structure. If the stimulus presents a good argument, then the right answer must also be a good argument.
- CORRECT. This matches.
Grades ➞ Studying ➞ Time management
Some students raised grades. So some students study.
- This is a flawed argument, it makes an incorrect negation.
Reasoning: Consume ➞ manufacture
Conclusion: Consume ➞ manufacture
- This is a bad argument. There might be some other way to protect the ecosystems, other than government action.
- This is a bad argument. The argument didn’t say how the power for the replacements will be supplied. Maybe it will be supplied from renewable sources such as solar.
- This is a bad argument. Here’s the structure:
Reasoning: Well designed ➞ harmonize
Harmonize ➞ well designed ➞ expensive
Conclusion: Harmonize xor expensive
This answer says “or else”. That phrasing refers to the exclusive or: “one or the other, but not both”. The way to draw this logically is with the “xor” symbol.
The reason the argument is bad is that you could have a building that is expensive and also doesn’t harmonize. You can have the necessary condition (“expensive”) while also lacking the sufficient condition (“harmonize”). So this isn’t a xor relationship (“one or the other or not both”): you could instead have neither!
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