Circular Definition

Description: A circular definition is defining a term by using the term in the definition.  Ironically, that definition is partly guilty by my use of the term “definition” in the definition.  Okay, I am using definition way too much. Damn!  I just did it again.

Logical Form:

Term 1 is defined by using term 1 in its definition.

Example #1:

 Circular definition: a definition that is circular.

Explanation: The definition is not at all helpful because we used the same words in the term to define them.

Example #2:

Flippityflu: smarter than a Floppityflip.

Floppityflip: dumber than a Flippityflu.

Explanation: Here we have two definitions that result in a slightly larger circle, but a circle nonetheless.

Exception: Many definitions are circular, but in the process of defining, there might be enough other information to help us understand the term.

Ethics: moral principles that govern a person's behavior or the conducting of an activity.

Moral Principles: the principles of right and wrong that are accepted by an individual or a social group.

Principles of Right and Wrong: moral principles or one's foundation for ethical behavior.


Lavery, J., & Hughes, W. (2008). Critical Thinking, fifth edition: An Introduction to the Basic Skills. Broadview Press.

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