Hello, I’m Pang Ying. Welcome to the Q&A for Episode 6 of Think Like a Debater.

The conclusion is factually true: cats are living things. But do we know this from outside knowledge, or has the syllogism established it through valid inference?

First examine the premises. Both “all living things need water” and “cats need water” are factually true.

Now examine the structure and identify the middle term. Water appears in both premises, so it is the middle term. Yet in both it is a predicate and particular rather than referring to all water; the middle term is therefore undistributed.

In “all living things need water,” living things are universal. In “cats need water,” all cats are meant, so cats are universal. Water, as predicate, is not universal; the middle term remains undistributed.

Thus “cats are living things” happens to be true. We judge it true through common knowledge, not through value created by this syllogism.

A syllogism is an inferential structure. With true premises and a valid structure, its conclusion must be true. We need no outside information to judge the conclusion and need not already know its subject matter.

In other words, if premises and structure are valid, you need not know in advance whether cats are living things; the syllogism will tell you.

Replace the content while retaining the same invalid form and the problem becomes clearer.

I need say no more; you know whether that is right or wrong.