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=                    Jungian cognitive functions                     =
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                             Introduction
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Cognitive functions, also referred to as psychological functions, as
described by Carl Jung in his book 'Psychological Types', are
particular mental processes within a person's psyche that are present
regardless of common circumstance. This was a concept that served as
one of the conceptual foundations for his theory on personality type.
In his book, he noted four main psychological functions: 'thinking',
'feeling', 'sensation', and 'intuition'. He introduced them with
having either an internally focused ('introverted') or externally
focused ('extraverted') tendency which he called "attitudes".


                               History
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Jung originally conceived of the model in which four cognitive
functions combine to form different psychological types. This was done
in his work 'Psychological Types', published as the sixth volume in
'The Collected Works of C. G. Jung.' Jung posited that the functions