Primary
Purpose

Master the most fundamental LSAT Reading Comprehension question type: identifying the author's main goal for writing the passage.

LSAT Reading Comprehension

What is Primary Purpose?

Every LSAT Reading Comprehension passage is written with a single overarching goal. The "Primary Purpose" question asks you to identify why the author wrote the passage: not what the passage says, but what the author is trying to accomplish.

Why Primary Purpose Matters

High Frequency

Nearly every RC passage includes at least one Primary Purpose question: it is the most common question type.

Foundation Skill

Correctly identifying the purpose helps you answer other question types: tone, organization, and author agreement.

Time Saver

When you read with purpose in mind, you process the passage faster and avoid rereading.

Recognizing the Question Stem

Primary Purpose questions use distinctive phrasing. Learn to spot these stems instantly so you know exactly what the question demands.

1

"Which one of the following most accurately expresses the main point of the passage?"

2

"The primary purpose of the passage is to..."

3

"Which one of the following best describes the main purpose of the passage?"

4

"The passage is primarily concerned with..."

The Core Rule

Author Action Verbs

LSAT answer choices for Primary Purpose almost always begin with an action verb that describes what the author is doing. Learning to decode these verbs is essential.

Argue / Advocate

The author takes a clear position and defends it with reasoning.

Describe / Explain

The author neutrally presents information without strong advocacy.

Evaluate / Assess

The author weighs the merits and drawbacks of a position or theory.

Challenge / Critique

The author opposes a prevailing view and presents counterarguments.

Main Point vs. Primary Purpose

	Main Point	Primary Purpose
Asks	What does the author conclude?	Why did the author write this?
Answer Form	A specific claim or thesis	An action verb + general scope
Example	"Digital archiving preserves access better than microfilm"	"To argue that a particular method is superior"
Specificity	Highly specific to passage content	Broader: captures the type of goal

The 4-Step Method

1

Read for the "Why." As you read, continually ask: "Why is the author telling me this?" Note shifts in tone and direction.

2

Formulate a prediction. Before looking at the choices, complete this sentence in your own words: "The author wrote this passage in order to ___."

3

Check the verb. Match the action verb in each answer choice against the author's tone. Is the author arguing, describing, challenging, or reconciling?

4

Check the scope. Eliminate answers that are too narrow (one paragraph only) or too broad (beyond the passage's actual coverage).

The Scope Spectrum

Example 1: Science Passage

P1

The passage opens by describing a traditional theory of coral reef formation and notes its wide acceptance among marine biologists.

P2

New evidence from deep-sea drilling is presented that contradicts the traditional theory.

P3

The author introduces an alternative explanation and argues it better accounts for the drilling data.

P4

The passage concludes by noting implications of the alternative theory for future research.

Example 1: Eliminating Traps

✕ "To describe deep-sea drilling techniques"

Too narrow. Drilling is evidence, not the author's purpose.

✕ "To summarize the history of marine biology"

Too broad. The passage addresses one specific debate, not the whole field.

✕ "To explain coral reef formation"

Wrong verb. The author doesn't just explain: the author argues for a side.

✓ "To challenge an accepted theory and propose an alternative"

Correct scope + verb. Matches the entire passage and the author's argumentative tone.

Example 2: Law Passage

P1

Introduces two competing interpretations of the Fourth Amendment's protection against unreasonable searches.

P2

Describes how each interpretation has been applied in case law, noting strengths and weaknesses of each.

P3

The author does not take a strong side but suggests that both interpretations have merit in different contexts.

Example 3: Humanities Passage

A passage begins by noting that literary critics have traditionally dismissed a novelist's later works as inferior. The author then presents evidence that these later works were innovative in ways critics missed, and concludes that the novelist's reputation deserves reassessment.

Tone Clue

The author disagrees with the prevailing critical view. This is argumentative, not merely descriptive.

Scope Clue

Covers a specific novelist's later works: not all of literature, and not just one novel.

Common Mistakes

✕ Picking a Detail

Choosing an answer that accurately describes one paragraph but ignores the rest of the passage.

✕ Wrong Action Verb

Selecting "describe" when the author is clearly arguing, or "challenge" when the author is neutral.

✕ Scope Creep

Choosing an answer that is true of the general topic but goes beyond what this specific passage covers.

Quick Reference Table

Passage Type	Typical Purpose Verb	Tone Signal
Advocacy	argue, contend, advocate	Strongly supports one side
Critique	challenge, question, undermine	Opposes an existing view
Comparison	evaluate, compare, weigh	Balanced: presents multiple sides
Exposition	describe, explain, outline	Neutral, informational
Reconciliation	reconcile, resolve, synthesize	Shows how opposing views can coexist

Question 1 of 5

A passage describes how traditional economic models assume rational decision-making by consumers. The author then introduces findings from behavioral economics showing systematic irrationality and argues that these findings require a fundamental rethinking of economic policy, since policies based on the assumption of rationality are likely to be ineffective.

▼ Tap to read passage

The primary purpose of this passage is to:

The author doesn't just describe or explain: the author argues that policy needs to change. Choice (B) is too narrow (covers only the findings, not the policy argument), while (A) is too broad and (D) contradicts the author's positive use of behavioral economics.

Question 2 of 5

A passage presents two competing theories about why certain bird species migrate at night. The first theory emphasizes predator avoidance, while the second emphasizes thermoregulatory advantages. The author examines evidence for both and concludes that neither theory alone is sufficient, suggesting that the phenomenon likely results from a combination of factors.

▼ Tap to read passage

Which one of the following best describes the main purpose of the passage?

The author evaluates two theories and concludes both have merit: this is a comparison/synthesis passage. (A) picks a side the author doesn't take. (C) misses the evaluative, argumentative structure. (D) is entirely unsupported.

Question 3 of 5

A passage discusses how a recent Supreme Court ruling expanded the definition of "public use" in eminent domain cases. The author traces the historical development of the doctrine, examines the court's reasoning in the recent case, and expresses concern that the ruling may erode property rights protections for individual homeowners.

▼ Tap to read passage

The passage is primarily concerned with:

The author critiques the ruling and warns about consequences. (A) and (B) are each too narrow: they describe parts of the passage but not the author's evaluative purpose. (C) goes too far: the author criticizes expansion, not the doctrine itself.

Question 4 of 5

A passage explains how three different cultures independently developed similar flood myths. The author presents the myths side by side, notes structural parallels, and discusses anthropological theories about why cultures with no known contact might produce remarkably similar narratives. The author does not favor any single theory but treats each as illuminating.

▼ Tap to read passage

Which one of the following most accurately expresses the primary purpose of the passage?

The author is descriptive and exploratory, not argumentative. (B) claims a position the author never takes. (C) mischaracterizes the author's neutral treatment of the theories. (D) introduces a question the passage never addresses.

Question 5 of 5

Critics have long held that the African American literary tradition was primarily shaped by the experience of slavery and its aftermath. A recent scholar counters that this view, while not entirely wrong, underestimates the influence of African oral traditions on the formal innovations found in African American literature. The scholar provides detailed analyses of three novels to demonstrate how techniques from West African storytelling were adapted into written English prose.

▼ Tap to read passage

The primary purpose of this passage is to:

The passage is structured around a scholar's counter-argument to prevailing criticism. (A) is too broad. (B) is too narrow: oral techniques are evidence, not the purpose. (D) is entirely unsupported: the author engages with criticism, not against it as a field.

PrimaryPurpose

What is Primary Purpose?

Why Primary Purpose Matters

Recognizing the Question Stem

The Core Rule

Author Action Verbs

Main Point vs. Primary Purpose

The 4-Step Method

The Scope Spectrum

Example 1: Science Passage

Example 1: Eliminating Traps

Example 2: Law Passage

Example 3: Humanities Passage

Common Mistakes

Quick Reference Table

Question 1 of 5

Question 2 of 5

Question 3 of 5

Question 4 of 5

Question 5 of 5

Primary
Purpose