What is intelligence? Luke Muehlhauser. Attempts an explanation of intelligence.

71 Definitions of Intelligence - Shane Legg. Reviews various explanations of intelligence. 

Possible Minds - John Brockman. Collection of essays about different mind architectures enabled by technology.

Society of Mind - Marvin Minsky. Classic on how intelligence on the level of the individual and society arises from individual agents cooperating with each other.

What is Intelligence? - Kurzgesagt. Intro-level explainer video defining intelligence.

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