October 2010 LSAT
Section 3
Question 3
Commentator: If a political administration is both economically successful and successful at protecting individual li...
Reply
SamA on January 19, 2020
Hello @caghjayan,Good question, it is important to be able to identify these for just about every LR question type. I will make an example with a premise, a sub-conclusion, and a main conclusion.
Remember that any conclusion requires support. A conclusion by itself will leave you asking, "Why?" or "How?" The premise is that support, as it answers these questions. Take a look at this example:
1. Watching football requires most of my attention. 2. Because of this, it is unlikely that I will get a good grade if I do homework while I watch the game. 3. I should listen to the radio broadcast instead while I study on Sunday.
Sentence 1 is our premise. It is a statement of fact that we must accept. It does not require further support. Refer to the fact vs. argument video in the Intro to Logical Reasoning lesson if this is unclear.
Sentence 2 is our sub-conclusion. It is unlikely that I will get a good grade. Why? Because watching football requires most of my attention. In the absence of sentence 3, this would be the primary conclusion. All conclusions must follow the premise-conclusion format. The phrase "because of this" tells us that this conclusion is based on sentence 1. Indicators like this help us follow the path of the argument. We can see that the premise led to this sub-conclusion.
Sentence 3 is the main conclusion. But how can we tell the difference between sentences 2 and 3? Why is one primary while the other is secondary? We have to think about which conclusion leads to which. In this case, sentence 2 leads to sentence 3. My "question and answer" strategy helps me see this relationship more clearly. Why should I listen to the radio broadcast? Because I will probably not get a good grade if I watch the game on TV. The sub-conclusion acts as a premise for the main conclusion.
It doesn't work the other way around. Why will I probably not get a good grade if I study while I watch the game? Because I should listen to the radio broadcast instead. This doesn't make sense. Sentence 3 is the end of the line. It is not meant to support anything else. It is our main conclusion.
I hope that is helpful.
A principle is a general rule or statement, often given in our conditional sufficient and necessary format. For example:
People who live in glass houses (LGH) should not throw stones (not TS).
LGH - - - - - - - - - > not TS
Animals with cold blood (CB) do not mate for life (not MFL).
CB - - - - - - - > not MFL
MFL - - - - - - -> not CB