Reasoning & Commentary

You’ll be able to

Explain the role of commentary in linking evidence to a claim
Identify the unstated assumption (warrant) that connects evidence and claim
Strengthen an argument by making its reasoning explicit

Commentary: the reasoning between the lines

Commentary is your explanation of how a piece of evidence supports your claim. Evidence rarely speaks for itself; commentary is where the actual arguing happens. If evidence is the "what," commentary is the "so what." Weak writers assume the connection is obvious and skip it; strong writers spell it out: This detail matters because it shows… The ratio to aim for is more commentary than evidence — a quotation followed by two or three sentences unpacking its significance, not the other way around.

The warrant: the hidden assumption

Between every claim and its evidence lies a warrant — the underlying assumption that makes the evidence count. If I claim "she will be a good doctor" because "she is compassionate," the warrant is "compassion makes a good doctor." Warrants are usually unstated, and arguments break down when the audience does not share them. Skilled arguers surface their warrants when an audience might reject them, defending the assumption itself. Spotting the warrant lets you see why an argument works — or where it is quietly vulnerable.

Building a line of reasoning

Individual claims must connect into a line of reasoning — a logical sequence where each point sets up the next and all point back to the thesis. Commentary is the connective tissue: it shows how one piece of evidence advances the argument and hands off to the following one. A reader should be able to trace an unbroken path from the first paragraph to the conclusion. When commentary is missing, the essay becomes a list of evidence with no through-line, and the argument stalls even if every fact is true.

Worked example

Identify the claim, evidence, and warrant, then supply the missing commentary: "The mayor cannot be trusted with the budget. Last year he overspent by two million dollars."

1.Claim: the mayor cannot be trusted with the budget.
2.Evidence: last year he overspent by two million dollars.
3.Warrant (unstated): a leader who overspends once cannot be trusted to manage money — past overspending predicts future mismanagement.
4.Supply commentary that makes the reasoning explicit and tests the warrant: a two-million-dollar overrun signals either poor forecasting or weak discipline, and because budgeting is a core mayoral duty, that failure bears directly on his fitness — unless the overspending had an extraordinary, one-time cause.

Answer: The argument rests on the unstated warrant that a single overspend predicts ongoing mistrust. Making it explicit ("a two-million-dollar overrun signals poor forecasting or weak discipline, and budgeting is a core duty") both strengthens the reasoning and exposes its weak point — one anomalous year might not warrant the sweeping claim.

Checkpoint

In the argument "This candidate will protect the environment because she rides a bicycle to work," what is the unstated warrant?

Tip

After each quotation, force yourself to write the words "This matters because…" and finish the sentence. Then delete the crutch phrase. What remains is commentary. If you cannot finish the sentence, the evidence may not belong.

Checkpoint

An essay presents ten well-chosen quotations but almost no explanation between them. According to the AP argument rubric, what is the essay’s most likely weakness?

On the exam

The AP evidence-and-commentary row tops out only when commentary "consistently explains how the evidence supports the line of reasoning." Aim for a 2:1 commentary-to-evidence ratio — after every quote, out-explain it. Listing evidence caps your score; explaining it uncaps it.

Answer the 2 checkpoints as you read.