“Never argue with a six-year-old who shaves.”
Bill Watterson Calvin and Hobbes
Source: Calvin and Hobbes
A Slave is a Slave (1962)
Context: Oh, he won't think of it in those terms. He'll be preventing me from sabotaging the Emancipation. He doesn't want to wait three generations; he wants to free them at once. Everything has to be at once for six-month-old puppies, six-year-old children, and reformers of any age.
“Never argue with a six-year-old who shaves.”
Bill Watterson Calvin and Hobbes
Source: Calvin and Hobbes
Ken Robinson (1950) UK writer
TED Conference http://www.ted.com/talks/sir_ken_robinson_bring_on_the_revolution.html (2010)
“If you can't explain it to a six year old, you don't understand it yourself.”
Albert Einstein (1879–1955) German-born physicist and founder of the theory of relativity
Variant: If you can't explain it to a six year old, you don't understand it yourself.
Peter J. Carroll (1953) British occultist
Source: PsyberMagick (1995), p. 35
“I am a hundred and forty six years old and this is not my first unwinnable war.”
Cassandra Clare book City of Heavenly Fire
Source: City of Heavenly Fire
Isaac Asimov (1920–1992) American writer and professor of biochemistry at Boston University, known for his works of science fiction …
Asimov Laughs Again (1992)
General sources
Judith Martin (1938) American etiquette expert
Miss Manners' Guide to Excruciatingly Correct Behavior
“Can you giggle while racing for your life and protecting a six-year-old? I can.”
James Patterson (1947) American author
Source: Maximum Ride The Angel Experiment