From entry System 1 in glossary Artificial Intelligence: humans at the heart of algorithms
In Daniel Kahneman's "Thinking, Fast and Slow", System 1 refers to the rapid unconscious processes that allow instant reactions, for example, if you start to slip, or you reach to catch an approaching ball. It is in contrast to System 2, which is slower more reasoned thinking. System 1 is rapid, but may be hard to explain to others. In AI, neural networks and subsymbolic AI in general correspond closely to human System 1 thinking.
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