Extropy is a proposed opposing concept to entropy. As entropy decreases , signifying more order, so extropy would increase in the manner of negentropy. Extropy also attempts to describe the nature of the order, so a crystal , although highly ordered would have low extropy, but an organism or machine would have high extropy because of the informational structure contained within it. Extropy also describes the tendency of systems to grow more organized. The idea was first introduced by philosopher and futurist Max More in the late 1980s.
The term was first coined to serve as an antonym of entropy, replacing its prefix (representing the prepositional prefix ἐν en, “in” in its Ancient Greek etymon ἐντροπία entropía “a turning towards”) with ex- (representing the Ancient Greek ἐξ ex “out of”, “from”); although, because ἐξ eks takes the form ἐκ ek when prefixed to an element beginning with τ (t), the analogical spelling is ectropy (or ektropy), as if from Ancient Greek *ἐκτροπία (ektropía “a turning out of”).
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