Knowledge is knowing a tomato is a fruit; wisdom is not putting it in a fruit salad.

Miles Kington, a British journalist and humorist, is widely credited with this line as part of his broader comic interest in the gap between abstract knowledge and practical judgment. The quip circulates primarily as an aphorism in quotation collections and on the internet rather than as a reliably pinned-down remark from a specific dated speech or interview. It fits Kington’s characteristic style: using a homely, everyday example (food and social etiquette) to puncture pedantry and to show how “being right” in a technical sense can still miss the point in real life. The tomato example draws on a familiar botanical fact that many people “know,” but rarely apply socially.

The joke hinges on the gap between technical correctness and practical judgment. “Knowledge” is factual: botanically, tomatoes are fruits because they develop from a flower and contain seeds. “Wisdom” is contextual: in cooking and taste, tomatoes behave like savory ingredients, so treating them like sweet fruit can be misguided. The aphorism humorously argues that intelligence isn’t just accumulating true statements; it’s knowing how to apply them appropriately. It also gestures at the limits of classification systems: a label can be accurate yet unhelpful if it ignores purpose, convention, and human experience.

“Knowledge is knowing that a tomato is a fruit; wisdom is knowing not to put it in a fruit salad.”
“Knowledge is knowing a tomato is a fruit. Wisdom is not putting it in a fruit salad.”
“Knowledge is knowing the tomato is a fruit; wisdom is not putting it in a fruit salad.”