Chapter 1

Foundations of Watson-Glaser Reasoning

By A S Prasad, Critical Thinking Academy

The Watson-Glaser Critical Thinking Appraisal has one purpose: to measure how well you reason. It doesn't test what you know, but how you think. The assessment evaluates your ability to analyse information, follow logic, and judge arguments objectively. Success depends on your skill in logical reasoning — not on memorising facts or formulas, but on thinking clearly and systematically about the information you're given.

Part 1: What the Watson-Glaser Measures

The Watson-Glaser is built around a specific model of critical thinking called the RED model:

The test measures these three skills as indicators of your critical thinking capability. To test these skills, the Watson-Glaser evaluates your performance across five specific areas:

Part 2: The Language of the Test

To do well on the test, you need to understand logical reasoning — the core skill in critical thinking. This book uses Watson-Glaser terminology throughout, so you won't be confused when you see the actual test.

Logical reasoning has three core terms:

Conclusion: What the argument tries to convince you of.

Reason: A statement that supports the conclusion by justifying it.

Argument: A conclusion along with its supporting reason or reasons.

In logical reasoning, an argument is not a quarrel or disagreement. It's simply a conclusion supported by reasons.

A note on Watson-Glaser format

On the Watson-Glaser, the "Argument" field presents arguments in compressed form. Here is what this looks like:

The YES means: "Yes, we should invest in employee training programs because..." The YES or NO represents the conclusion. The text after the semicolon provides the reason. When you analyse these arguments, mentally expand the YES or NO into the full conclusion. The complete argument reads as: [YES, we should invest in employee training programs] because [such programs have been shown to increase productivity by up to 15%].

Part 3: Two Techniques

Technique 1: The "Because" Test

To see how the parts of an argument fit together, use a simple mental check: insert the word "because" between the conclusion and the reason. This turns the argument into one clear sentence:

The "Because Test" helps you put the argument into a logical structure, making it easier to see whether the reason supports the conclusion. The test itself does not tell you whether the argument is strong or weak — you still need to evaluate the reasoning. But it gives you a clear framework for understanding what the argument is claiming.

Technique 2: Judging an Argument as Strong or Weak

In the Evaluate Arguments section, your goal is to decide whether an argument is Strong or Weak. This decision follows a two-part test:

1. Is the reason relevant? Does it directly support the conclusion?

2. Does the reason provide adequate grounds? Assuming the reason is true, does it give sufficient support to accept the conclusion as reasonable?

A Strong Argument passes both tests. A Weak Argument fails at least one — either the reason is not relevant to the conclusion, or it does not provide adequate support, or it fails on both counts.

Exercises: Deconstructing Arguments

In these exercises, you'll practise identifying Conclusions and Reasons, and applying the "Strong vs. Weak" framework using the Because Test.

For each argument below:

• Identify the Conclusion and the Reason.
• Mentally apply the Because Test: "(This is the conclusion) because (this is the reason)."
• Judge the argument as Strong or Weak based on relevance and adequate grounds.