Argument Structure & Keyword Indicators

What You Need to Know

Argument structure is how an LSAT stimulus is built: which sentence is the main conclusion, which ones are premises, what’s just background, and whether there are subconclusions, objections, or concessions.

Why it matters: almost every LR question type (Strengthen/Weaken, Assumption, Flaw, Method, Main Point, Inference, etc.) becomes easier when you can quickly label the parts.

Core definitions (use these labels mentally)

  • Conclusion: the claim the author is trying to prove.
  • Main conclusion: the “top-level” claim supported by everything else.
  • Premise: support offered for a conclusion (facts, data, studies, generalizations, examples).
  • Intermediate conclusion / Subconclusion: a conclusion supported by premises that then supports the main conclusion.
  • Counterpremise: a statement that supports the opposite of the author’s conclusion (often introduced as what “some people claim,” “critics argue,” etc.).
  • Concession: a point the author grants (often “although…”) but then pivots to their real conclusion.
  • Background / Context: information that sets the scene but isn’t offered as support.
  • Qualification: limits the strength/scope (e.g., “most,” “some,” “often,” “probably”). These matter for matching answer choices.

The key rule

Don’t trust keywords blindly. Many indicators are ambiguous in everyday English (e.g., “since,” “as,” “so,” “thus”), and the LSAT exploits that. Use keywords as clues, then confirm by meaning: Which claim is being supported, and which claim is doing the supporting?

Critical reminder: A statement can be true and still be a conclusion (if it’s what the author is trying to establish in that argument). “Conclusion” is a role, not a truth-value.

Step-by-Step Breakdown

Use this fast procedure on any LR stimulus.

1) Skim for the author’s “point” (candidate conclusion)

Look for conclusion indicators (see tables below), especially near the end. Then ask:

  • “What is the author trying to convince me of?”
  • “If I had to argue against this passage, what would I attack?” (often the conclusion)

2) Find support for that candidate conclusion

Underline/mentally tag reasons. Premises often:

  • cite evidence (“studies show…,” “the survey found…”)
  • state facts or patterns
  • give causal explanations offered as support

Quick check: If statement A is offered to make statement B more likely, then A is a premise and B is a conclusion.

3) Watch for pivots: concession/counterargument + author’s response

Common LSAT structure:

  • “Some people say X… however Y… therefore Z.”
    Here, X is usually a counterpremise or objection, Y is the author’s reply (often a premise), and Z is the author’s conclusion.

4) Test for intermediate conclusions

If you see a chain like:

  • Evidence → Claim 1 → Claim 2
    Then Claim 1 is an intermediate conclusion.

Mini-annotation example:

  • “The river’s toxin levels have doubled in the last year. So the new factory is polluting the river. Therefore, regulators should fine the factory.”
    • Premise: toxin levels doubled
    • Intermediate conclusion: factory is polluting
    • Main conclusion: regulators should fine

5) Separate argument vs explanation (big trap)

  • Argument: gives reasons to believe a claim.
  • Explanation: assumes a claim is true and explains why it happened.

Fast diagnostic:

  • If the stimulus treats the phenomenon as already established and answers “Why did this happen?”, it’s often an explanation.
  • If the stimulus is trying to prove the phenomenon is true, it’s an argument.

Keyword clue: “because” can introduce either (premise in an argument or cause in an explanation). Confirm by role.

6) Map multiple conclusions carefully

Sometimes the author makes two conclusions:

  • Main conclusion + recommendation (“Thus, the city should…”)
  • Or two parallel conclusions (“Therefore A, and B.”)
    Choose the one supported by the rest as the main.

Key Formulas, Rules & Facts

Keyword indicators (most common, high-yield)

Conclusion indicators
IndicatorWhat it usually signalsNotes / traps
thereforeconclusionvery reliable
thusconclusionpretty reliable; can be summary
henceconclusionreliable
soconclusionambiguous: can mean “therefore” or just flow of speech
consequentlyconclusionreliable
as a resultconclusion (often causal)can also mark an effect statement used as premise
it follows thatconclusionreliable
we can conclude thatconclusionvery reliable
this shows/proves thatconclusion“shows” can also introduce a premise about evidence
clearly/obviouslyconclusion emphasisnot a logical guarantee; still just rhetoric
should/oughtoften conclusion (recommendation)watch for “should” as premise in normative chains
Premise indicators
IndicatorWhat it usually signalsNotes / traps
becausepremisecan also introduce explanation; confirm role
sincepremiseambiguous: can be temporal (“since 2010”)
forpremise“for” = “because” (formal usage), not “for example”
given thatpremisereliable
after allpremisevery common LSAT premise marker
in thatpremisereliable but less common
as indicated bypremise/evidenceoften introduces data
the fact thatpremiseoften introduces a key supporting fact
assuming thatpremise (conditional support)may signal a hypothetical premise
Contrast / concession / counterargument indicators
IndicatorWhat it usually signalsNotes / traps
however / but / yetpivot to author’s real viewoften follows a concession or counterpoint
although / even though / thoughconcessionwhat follows may be background or conceded premise
nevertheless / nonethelessauthor’s conclusion despite concessionstrong pivot
on the other handalternative viewmay introduce counterpremise
some people claim / critics arguecounterpremise/objectionusually not author’s view
despite / in spite ofconcessionflags “this doesn’t change my conclusion”

Structural rules you can rely on

  • Main conclusion is the statement that the author ultimately wants you to accept; other conclusions (if any) support it.
  • Premises can be indirect: a premise can support another premise, or support an intermediate conclusion.
  • Background ≠ premise: a scene-setter might be true but is not used as support.
  • Quantifiers matter: “some,” “most,” “all,” “many,” “rarely,” “only,” “unless,” “typically,” “probably.” These often create wrong answer traps if you shift strength.

Common “hybrid” indicators (need confirmation by meaning)

Word/phraseCould indicateHow to disambiguate quickly
soconclusion or fillerAsk: is what follows supported by prior claims?
as a resultconclusion or premise (effect)Effect statement could be used as evidence for a cause
sincepremise or timeIf it can be replaced with “because,” it’s premise; if it answers “since when,” it’s time
thusconclusion or restatementIf it adds a new claim, likely conclusion; if it paraphrases, it’s summary
thenconditional step or timelineCheck if it’s “if…, then…” vs sequence
for examplesupport or illustrationUsually supports a general claim, but examples can be background if not used to prove

Examples & Applications

Example 1: Classic conclusion + premises

Stimulus:

“People who regularly sleep fewer than six hours have higher rates of workplace accidents. Therefore, employers should encourage workers to get more sleep.”

How to label:

  • Premise: short sleepers have higher accident rates
  • Conclusion: employers should encourage more sleep

LSAT angle:

  • Strengthen/Weaken will target whether encouragement leads to more sleep and reduces accidents.
  • Assumption may involve “encouraging” being effective or within employer control.

Example 2: Concession + pivot (don’t pick the conceded point)

Stimulus:

“Although some electric cars are expensive upfront, their lower fuel and maintenance costs make them cheaper over the long term. Thus, for most commuters, electric cars are the more economical choice.”

Labels:

  • Concession/background: some electric cars expensive upfront
  • Premise: lower fuel/maintenance makes cheaper long term
  • Main conclusion: for most commuters, electric cars more economical

Keyword takeaway:

  • “Although” introduces something you shouldn’t treat as the author’s point.
  • “Thus” is your conclusion flag.

Example 3: Counterargument + author response

Stimulus:

“Critics say the museum’s new exhibit is historically inaccurate. However, the exhibit’s descriptions are drawn directly from primary-source letters. So the exhibit is historically accurate.”

Labels:

  • Counterpremise/objection: critics say inaccurate
  • Premise (author’s support): descriptions drawn from primary-source letters
  • Conclusion: exhibit is historically accurate

Question-type tie-in:

  • Flaw/Weaken often attacks the jump from “primary-source letters” to “accurate” (letters could be biased, unrepresentative, misinterpreted).

Example 4: Intermediate conclusion chain

Stimulus:

“The company’s profits rose after it reduced product defects by half. Since fewer defects typically reduce returns and warranty costs, the defect reduction caused the profit increase. Therefore, to increase profits further, the company should invest more in quality control.”

Labels:

  • Premise: profits rose after defects reduced
  • Premise: fewer defects typically reduce returns/warranty costs
  • Intermediate conclusion: defect reduction caused profit increase
  • Main conclusion: company should invest more in quality control

Structure insight:

  • “Therefore” introduces the recommendation (main conclusion).
  • The causal claim is doing support work (intermediate conclusion), and causal reasoning is a favorite LSAT target.

Common Mistakes & Traps

1) Keyword autopilot

  • What goes wrong: You see “since” or “so” and instantly label premise/conclusion.
  • Why wrong: Many indicators are ambiguous; LSAT loves “since 2018…” or conversational “so.”
  • Fix: Always verify by function: is it supporting or supported?

2) Mistaking a concession for the conclusion

  • What goes wrong: You choose the “although…” clause as the author’s point.
  • Why wrong: Concessions are often granted to sound fair, then the author pivots.
  • Fix: Hunt for the pivot (“however,” “nevertheless”) and the claim that follows it.

3) Confusing counterpremises with the author’s view

  • What goes wrong: You attribute “critics claim…” to the author.
  • Why wrong: That’s usually an opposing view being introduced to be rebutted.
  • Fix: Ask, “Is the author endorsing this, or setting it up to knock down?” Look for rebuttal markers.

4) Treating background facts as premises

  • What goes wrong: You over-label every factual sentence as support.
  • Why wrong: Some facts only set context and aren’t used to prove anything.
  • Fix: For each sentence, ask: “What claim does this help establish?” If “none,” it’s background.

5) Missing intermediate conclusions

  • What goes wrong: You think there’s only one conclusion, but actually there’s a chain.
  • Why wrong: Many Method/Flaw questions depend on recognizing the middle step.
  • Fix: If a statement is supported by earlier evidence and used to support a later claim, tag it as intermediate.

6) Explanation vs argument mix-up

  • What goes wrong: You assume every “because” structure is an argument.
  • Why wrong: Explanations give causes for accepted facts; arguments try to prove.
  • Fix: Identify the “surprising fact” being explained vs the “claim being proven.”

7) Scope/strength drift when paraphrasing conclusions

  • What goes wrong: Stimulus says “most” and you remember “all,” or “probably” becomes “definitely.”
  • Why wrong: Wrong answer choices often shift quantifiers/modality.
  • Fix: Keep qualifiers attached to the claim when you summarize.

8) Misreading recommendations and value judgments

  • What goes wrong: You label “we should do X” as a premise because it’s not factual.
  • Why wrong: Recommendations are frequently the main conclusion.
  • Fix: If other statements are offered to justify the “should,” it’s the conclusion.

Memory Aids & Quick Tricks

Trick / mnemonicWhat it helps you rememberWhen to use it
“Why?” testPremises answer “Why (believe that)?”; conclusions are what you’re answeringAny time you’re unsure which claim is supported
“Therefore” substitutionIf you can naturally put “therefore” in front of a sentence, it’s likely a conclusionWhen indicators are missing or ambiguous
Pivot hunt“Although/Some say…” then “however/nevertheless…” = author’s real move is after pivotWhen you see debate-like language
Concession sandwichConcession → Author reason → ConclusionCommon LR structure; keeps you from picking the wrong sentence
Chain checkEvidence → Subconclusion → Main conclusionWhen you see multiple “thus/therefore/so” or layered claims
Role labels, not truth labels“Conclusion” = what they’re trying to prove, even if it’s a fact-sounding sentencePrevents you from assuming facts can’t be conclusions

Quick Review Checklist

  • Identify the main conclusion: the claim the author ultimately wants you to accept.
  • Label premises as anything offered to support that conclusion (directly or indirectly).
  • Watch for pivots: “although/some say…” vs “however/nevertheless…”
  • Actively check for an intermediate conclusion when the reasoning feels multi-step.
  • Don’t let ambiguous keywords (“since,” “so,” “as a result”) do the thinking for you.
  • Keep qualifiers (“most,” “some,” “likely”) attached to the statement they modify.
  • Separate argument (prove a claim) from explanation (explain an accepted fact).

You don’t need to read faster—you need to label smarter, and this is one of the highest-return skills on LR.