I have yet to see a clear distinction/explanation between and 'necessary assumption' and a 'necessary condition' (right side of logic arrow). They seem to be used without a clarification on the differences in meaning or application. There is a little bit of confusion here. NA seem to be different in the use of analyzing the argument vs NC are clearly defined as the right side of the logic arrow.
I think of Necessary Assumptions as the foundation an argument depends on in order to function at all. A necessary assumption is something that must be true for the reasoning to apply, even if it does not guarantee the conclusion. For example, consider the argument: “All human beings are moral; therefore, I am moral.” A necessary assumption is that I am a human being. If that assumption were false, the premise would not apply to me, and the argument would collapse. The assumption does not prove the conclusion by itself, but without it, the argument cannot even be made.
Can someone explain the differences between this and Must Be True questions? For both answers, my current understanding is that if negated/falsified, the argument falls apart. Is one just stating the obvious, and another says something specific to the content of the stimulus?
Another good way to look at it is what the answer does.
Sufficient Assumptions are strong answers that make the conclusion stronger. They are there to beef up the logic and make it more likely to be true.
Necessary assumptions on the other hand are not trying to prove or strengthen anything. Necessary assumptions are proved by the information already in the stimulus. They are almost always weaker than SA because their purpose is not to prove the conclusion correct but to be required by the logic of the Existing facts. They are often unassuming almost "Duh, obviously" type answers. Be careful not to fall into the trap of thinking that an NA answer is too weak to be right. It is not supposed to be powerful, but provable.
Could an assumption be both necessary and sufficient or are they two totally separate things? I'm trying to think of a possibility where they could overlap, but haven't really thought of one so far.
Quick clarification about the difference between sufficient assumption and necessary assumption: So for SA, the assumptions do make the argument "better" while for the necessary condition they may not make the argument better but they are required for the argument to stand, correct?
One way I like to think about the difference in approaching necessary assumption questions versus sufficient assumption questions is the idea that both types of answer choices will be premises, but the premises are of a different sort. On one hand, necessary assumption answer choices are going to be premises that must be present in order for the conclusion to follow properly (NA - conclusion based). On the other hand, sufficient assumption answer choices are going to be premises that allow the argument to be valid in comparison to its conclusion (SA - argument based).
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349 comments
I have yet to see a clear distinction/explanation between and 'necessary assumption' and a 'necessary condition' (right side of logic arrow). They seem to be used without a clarification on the differences in meaning or application. There is a little bit of confusion here. NA seem to be different in the use of analyzing the argument vs NC are clearly defined as the right side of the logic arrow.
I think of Necessary Assumptions as the foundation an argument depends on in order to function at all. A necessary assumption is something that must be true for the reasoning to apply, even if it does not guarantee the conclusion. For example, consider the argument: “All human beings are moral; therefore, I am moral.” A necessary assumption is that I am a human being. If that assumption were false, the premise would not apply to me, and the argument would collapse. The assumption does not prove the conclusion by itself, but without it, the argument cannot even be made.
that actually helped me sm
that imovie-esque explosion of the argument at the end made me smile lol
I love this summary: Sufficient assumptions improve the argument but necessary assumptions may not though they are required.
Kobe was a horrible dude and if I were the prosecutor at his trial it would have gone down differently #motivation
Can someone explain the differences between this and Must Be True questions? For both answers, my current understanding is that if negated/falsified, the argument falls apart. Is one just stating the obvious, and another says something specific to the content of the stimulus?
I'm an English literature writer. Therefore, I'm one of the best writers in the country.
Necessary Assumption: I know how to use a pen.
I play basketball. Therefore, I am one of the best players in the world.
Necessary assumption: I am in the world.
I can eat a cheeseburger. Since its so tasty.
Nec Assumption: I can use my tastebuds
or, I can tell the difference between a burger and a piece of glass
Michael Jordan would get dominated by prime JY Ping, real hoopers will know
I can dribble a ball... that means I have a chance! Just like I have $248 meaning I have a chance at taking the LSAT. Thank you LSAC!
Thank you!! This example really helped me visualize the difference between the two in the context of an argument.
Derrick White will win 5 NBA championships and 5 MVPs
Another good way to look at it is what the answer does.
Sufficient Assumptions are strong answers that make the conclusion stronger. They are there to beef up the logic and make it more likely to be true.
Necessary assumptions on the other hand are not trying to prove or strengthen anything. Necessary assumptions are proved by the information already in the stimulus. They are almost always weaker than SA because their purpose is not to prove the conclusion correct but to be required by the logic of the Existing facts. They are often unassuming almost "Duh, obviously" type answers. Be careful not to fall into the trap of thinking that an NA answer is too weak to be right. It is not supposed to be powerful, but provable.
If I said, "there are few to no other basketball players in the world that are better than me. " Can that be a necessary assumption.
RIP Kobe
One thing that helped me to distinguish these questions:
1. Sufficient Assumption- ask myself, "Is it enough to know X?"
2. Necessary Assumption- ask myself, "Do I need to know X?"
Could an assumption be both necessary and sufficient or are they two totally separate things? I'm trying to think of a possibility where they could overlap, but haven't really thought of one so far.
Jaylen Brown is an exception to the knowing how to dribble
Quick clarification about the difference between sufficient assumption and necessary assumption: So for SA, the assumptions do make the argument "better" while for the necessary condition they may not make the argument better but they are required for the argument to stand, correct?
One way I like to think about the difference in approaching necessary assumption questions versus sufficient assumption questions is the idea that both types of answer choices will be premises, but the premises are of a different sort. On one hand, necessary assumption answer choices are going to be premises that must be present in order for the conclusion to follow properly (NA - conclusion based). On the other hand, sufficient assumption answer choices are going to be premises that allow the argument to be valid in comparison to its conclusion (SA - argument based).
Been trying to understand this concept for 9 months and JY just made it all make sense in 8 minutes and 13 seconds...
This is the video I've been looking for. LSAT+Basketball lovers community unite, it's like the colliding of my worlds lmao
What a grat lesson.