Categorical Logic·Guided Practice·Lesson 5 of 6

Evaluating Syllogisms by Rules and by Venn Diagrams

Applies the five classical rules of the syllogism to evaluate validity and introduces the three-circle Venn diagram as an alternative decision procedure, giving students two independent ways to check syllogistic arguments.

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In this lesson · 7 sections · 2 worked examples · 3 practice activities

The five classical rules
Rule 1 and Rule 2 in detail: distribution rules
Rules 3 and 4: quality rules
The Venn alternative: three-circle diagrams
…and 3 more

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