The Goldilocks principle is named by analogy to the children's story The Three Bears, in which a little girl named Goldilocks tastes three different bowls of porridge, and she finds that she prefers porridge which is neither too hot nor too cold, but has just the right temperature. Since the children's story is well known across cultures, the concept of "just the right amount" is easily understood and is easily applied to a wide range of disciplines, including developmental psychology, biology, astronomy, economics and engineering.
- In cognitive science and developmental psychology, the Goldilocks effect or principle refers to an infant's preference to attend to events which are neither too simple nor too complex according to their current representation of the world. This effect was observed in infants, who are less likely to look away from a visual sequence when the current event is moderately probable, as measured by an idealized learning model.
- In astrobiology, the Goldilocks zone refers to the habitable zone around a star: As Stephen Hawking put it, “like Goldilocks, the development of intelligent life requires that planetary temperatures be ‘just right’”. The Rare Earth Hypothesis uses the Goldilocks principle in the argument that a planet must neither be too far away from, nor too close to a star and galactic center to support life, while either extreme would result in a planet incapable of supporting life. Such a planet is colloquially called a "Goldilocks Planet". Paul Davies has argued for the extension of the principle to cover the selection of ‘our’’ universe from a (postulated) multiverse: “observers arise only in those universes where, like Goldilocks’ porridge, things are by accident ‘just right’”.
- In medicine, it can refer to a drug that can hold both antagonist (inhibitory) and agonist (excitatory) properties. For example, the antipsychotic Aripirazole causes antagonism of Dopamine D2 receptors in areas such as the Mesolimbic area of the brain (which show increased dopamine activity in psychosis), but also agonism of Dopamine receptors in areas of dopamine hypoactivity, such as the mesocortical area.
- In economics, a Goldilocks economy sustains moderate economic growth and low inflation, which allows a market-friendly monetary policy. A Goldilocks market occurs when the price of commodities sits between a bear market and a bull market. Goldilocks pricing is a marketing strategy that, although not directly related to the Goldilocks principle, uses product differentiation to offer three versions of a product to corner different parts of the market: a high-end version, a middle version and a low-end version.
- In communication, the Goldilocks principle describes the amount, type and detail of communication necessary in a system to maximize effectiveness while minimizing redundancy and excessive scope on the "too much" side and avoiding incomplete or inaccurate communication on the "too little" side.
- In mathematics, the "Goldilocks Zone" is often used to refer to the near horizontal "shelf area" of many third-degree – and higher – polynomials such as ƒ(x)=x³. It is sometimes strictly-defined as the area between which the slope of the first-order derivative does not exceed ±15° from the horizontal; although, less popular definitions based on rates of change are sometimes used.
- "The Story of Goldilocks and the Three Bears".
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- Kidd, Celeste; Piantadosi, Steven T.; Aslin, Richard N. (23 May 2012). "The Goldilocks Effect: Human Infants Allocate Attention to Visual Sequences That Are Neither Too Simple Nor Too Complex". PLOS ONE. 7 (5): e36399. Bibcode:2012PLoSO...736399K. doi:10.1371/journal.pone.0036399. PMC 3359326. PMID 22649492 – via PLoS Journals.
- S Hawking, The Grand Design (London 2011) p. 194
- Weingroff, Marianne. "Activity 1 Teacher Guide: The Goldilocks Principle".
- Muir, Hazel (25 April 2007). "'Goldilocks' planet may be just right for life". New Scientist. Retrieved 2 April 2009.
- "The Goldilocks Planet". BBC Radio 4. 31 August 2005. Retrieved 2 April 2009.
- P Davies, ‘’The Goldilocks Enigma’’ (London 2006) p. 298
- "Goldilocks communication: Just the right amount of information". 18 May 2011.
- Nolan, Jennifer (2000). Maths Quest 11 (PDF). John Wiley. p. 188.