Someone who likes things 'just right'—not too much or too little; also the fairytale character from the children's story.
From the English fairytale 'Goldilocks and the Three Bears,' first published in the 19th century. The character had golden hair, hence the name.
The 'Goldilocks principle' is now serious science—astronomers use it to describe habitable zones around stars, and it shows how a fairytale about finding balance became fundamental to astrobiology.
The fairy tale character is explicitly female, and 'Goldilocks principle' (just right) has become cultural shorthand. When used for people/professionals, it risks infantilizing women.
For the principle itself (optimization, balance): use 'optimal balance' or 'just-right calibration' to avoid gendered tale reference. If narrative context is appropriate, use 'Goldilocks' neutrally.
["optimal balance","sweet spot","calibration principle"]
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