Assumptions & The Loophole

True or False:
If a conclusion is boring, it is more likely valid.

If a conclusion is wild, it is less likely to be valid.

True

What does a Sufficient Assumption do?

The S.A. proves the conclusion 100% true.
Anything is fair game.

S.A.s are…

POWERFUL!

Indications of an S.A. - not keywords.

Will
Always
Everything

They bridge the gap between the premises & conclusion

How does the Necessary Assumption relate to the conclusion? 

If the conclusion is true, the N.A. must also be true. 

True or False: The N.A. is proved by the conclusion.

True
It’s what the conclusion needs, not what it wants.

Indications of an S.A. - not keywords.

Boring, like a valid conclusion.
It’s basic and obvious. 

An N.A. is proved by the _____, just like a valid conclusion is proven by the _____.

conclusion
premises

What is the S.A., Conclusion, and N.A. proof chain?

Sufficient Assumption —> Conclusion —> Necessary Assumption

The Sufficient Assumption proves the conclusion, and in turn, the conclusion proves the necessary assumption. 

Break down this S.A., Conclusion, and N.A. chain:

Conclusion: This egg will break

S.A. The Hammer of Zeus comes down from the sky and crushes this egg

N.A. The egg is breakable

Hammer of Zeus —> Break this egg —> Egg is breakable

S.A.: We don’t need the Hammer of Zeus specifically - it could be the Hand of God, Poseidon’s Trident, or I decide to stomp this egg and crush it. This is just something that proves the conclusion.

Conclusion: The egg’ll break. How? Hammer of Zeus works to accomplish that. 

N.A.: The egg is breakable. It’s foundational and boring. The egg being breakable doesn’t prove that it will break, but it proves that the egg is breakable. If the N.A. wasn’t that the egg was breakable, it would be possible for the egg to not be broken, even if I decided to throw it against a wall. 

Explain each function of the table:

	Sufficient Assumptions	Necessary Assumptions
Powerful or Provable?	Powerful	Provable
Boring or Not Boring?	Not boring	Boring
Does this always prove the conclusion 100% true?	Yes	No
If the conclusion is true, does this have to be true?	No	Yes

PoP SA: Because if it says most, all, will, then it leads to the conclusion taking place.

PoP NA: Because without it, the conclusion would fail.

BoNB SA: Has to be something out there so that the job gets done.

BoNB NA: Proved by the conclusion.

PTC SA: If it didn’t prove the conclusion 100%, then the argument falls apart. We have to defend the conclusion.

PTC NA: If the Conclusion was “All great leaders are tall. Lincoln was a great leader. Therefore, Lincoln was tall.” and the NA is “Lincoln was not an exception to the rule about great leaders being tall”, then the argument can stand. But it doesn’t prove that he was tall because the premise “all great leaders are tall” could be flawed.

CIS SA: In the example about the egg’s breakability, it’s the Hammer of Zeus that breaks the egg. It’s supplemental. It could be that I curbstomp the egg and break it. Whatever proves the egg will break will do. 

CIS NA: The egg will break —> The egg is breakable. Without the NA, then the conclusion cannot take place. 

The Sufficient Assumption Test

Does (insert answer choice) prove the conclusion?
(If yes, then yay)

The Necessary Assumption Test

If the conclusion is true, must (insert answer choice) be true?

Would the argument fall apart if (insert answer choice) was false? 

(If yes, then yay)

If it picks a point in the premises and builds a bridge to the conclusion, it’s a(n) ________ assumption.

Sufficient!

The ______ assumptions probably seems super obvious and basic. 

Necessary!

The _____ assumption is keeping catastrophe at bay. Guarding against loopholes and gaps in logic is this assumption’s job. 

Necessary

The _____ assumption forces things to happen, instead of stating a more general rule.

Sufficient

True or False: If (premise), then (conclusion is the ideal set up, and you can find a sufficient assumption this way via the premises.

True

True or False: If (premise), then (conclusion is the ideal set up, and you can find a necessary assumption from the validity of the conclusion because the sufficient was activated.

True

If (premise), then (conclusion) construction is what type of assumption?

Sufficient and Necessary

What does the “What If” test do to the conclusion in terms of assumptions?

Premise 1: Soda has a lot of sugar and dyes.

Premise 2: But it isn’t always the soda that’s colored, but the can.

Conclusion: So, it’s the Ginger Ale cans that are green. 

SA: “What if…the Ginger Ale soda is also green? What if…sugar and dyes create colors in the soda and the color of the soda changes the cans to green, stripping the soda of color.” “What if…they author is red/green color blind?” The “What If” test on the SA helps you see possibilities on how the conclusion came to be. 

NA: “What if the author mistakes other colors for green.” The “What If” test on the NA helps bring out a flaw with the conclusion. In this case, it would be required that the author can actually see green and can correctly identify green. 

If the conclusion is no longer valid, then the loophole works. Loopholes are…

negated necessary assumptions.

Contrapositive assumption chain

~ = negated/not

~NA —> ~ Conclusion True —> ~SA

The Loophole Rules

1. Shall not negate premises (all premises are true. Focus on how they don’t add up and the relationship between all premises)

2. Shall not negate the conclusion (the loophole shows why it doesn’t have to be true, not that it isn’t true.)

3. You can always figure out the loophole.

4 Types of Loopholes

1. Dangling Variable

2. Secret Value Judgements

3. Secret Downsides

4. Assumed Universal Goals

The Dangling Variable Loophole

They are new words that appear in the conclusion, and not in the premises. The author pretends that these new words are “basically” the same as different words from the premises. Nothing is basically the same on the LSAT.

If the author doesn’t do the work to connect the premises and the conclusion exactly right, you cannot automatically do it for them. The author’s job is to probe something to us, and dangling variables are cheating.

Common Dangling Variable Phrases:

1. “Electronics” and “inventions”

2. “Accurate” and “consistent”

3. “Interest of shareholders” and “profits high”

4. “Better developed neural connections” and “greater influence on the brain”

5. “Detract from social development” and “reduction in time interacting with people”

6. “Diets higher in cholesterol” and “Western diets

The Secret Value Judgements Loophole

This occurs when the author gets judgmental in the conclusion. Judgments are a big deal on the LSAT. Authors can’t deem something moral or appropriate in the conclusion without defining what those words imply or mean in the premises. This loophole reminds the author that they can’t just assume a convenient definition of these loaded words.

Secret Value Judgements Phrases:

1. moral/immoral

2. should/shouldn’t

3. appropriate/inappropriate

4. prudent/imprudent

5. good/bad

6. right/wrong

Secret Downsides Loophole

This takes place when the author compares two things and says one of them is superior without giving you the full story. They’ll say their preferred choice has a few upsides, but your loophole will remind them of the secret downsides they’re not considering. 

“What if _____ has a major downside in comparison to the ______ its being compared to?”. “What if the argument’s preferred option has a big downside?”

We don’t know the benefits of the topic being snuffed, so that’s our loophole here. 

Assumed Universal Goals Loophole

This is about things that the author assumes everyone would want. They’re the goals you constantly see commercials about, typically. 

Do not assume that it’s common knowledge for everyone to want one of these things. Some people need to do the opposite of these. 

Loophole “What if they don’t want to do (assumed universal goal in question)”

Assumed Universal Goals Phrases:

1. losing weight

2. lowering cholesterol

3. making more money

4. being more successful

5. being healthier