In an argument, an author’s opinion or position on an issue is called a claim. Generally, there is one main claim, which is what the author is trying to get you to think, change, or do. That claim is supported by reasons — the justifications used to support the claim. These reasons are supported by concrete evidence — facts, statistics, examples, expert opinions, definitions, or anecdotes.
A strong argument will have multiple reasons that build together to support the main claim. Sometimes reasons act as sub-claims, which support the author’s position. For example:
(1) Taking naps during the workday increases an employee’s productivity. (2) Sleeping for just 20 minutes will increase alertness, prevent burnout, and improve memory. (3) Employees who are overtired are more likely to make costly mistakes, so taking a brief nap will improve the bottom line.
In this example, sentence 1 states the main claim, that naps increase productivity. Sentence 2 supports that claim with reasons, or sub-claims — examples of how naps provide specific benefits. Sentence 3 builds on these examples with another reason: naps are cost effective.
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