There's no fool like an old fool

Cultural  

1. The most extreme fools are people whose age should have made them wise.

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no fool like an old fool, there's Idioms  

1. An old fool is the worst kind of fool, as in He's marrying a woman fifty years his junior—there's no fool like an old fool. This adage, now considered somewhat offensive for stereotyping old people, appeared in John Heywood's 1546 proverb collection and has been repeated ever since.

2. see no fool like an old fool.

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