Baby, You're a Baby
A parent's baby talk ('You're a baby, Baby!') is compared to the near-circular definitions at the start of an axiomatic system.
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Free for classrooms, worksheets, slides and other non-commercial use under CC BY-NC 4.0, with credit to Ben Orlin.
Cartoon by Ben Orlin, Math with Bad Drawings. https://cartoons.mathwithbaddrawings.com/2019-11-18-baby-you-re-a-baby/ (CC BY-NC 4.0)Transcript
Parent (holding infant): "Baby! Hey, Baby! You're a baby, Baby!"
[Caption] "Every axiomatic system begins with trivialities, definitions that feel almost circular."