What do you call the personality type theory that gives people codes based on their levels of four major traits, including sensing-intuition or thinking-feeling?

The personality type theory that gives people codes based on their levels of four major traits, including sensing-intuition or thinking-feeling is called the Myers-Briggs.

The Myers–Briggs Type Indicator (MBTI) is an introspective self-report questionnaire designed to indicate psychological preferences in how people perceive the world and make decisions. The MBTI was constructed by Katharine Cook Briggs and her daughter Isabel Briggs Myers.

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i believe the answer is:   psychological  experiment

in this experiment, wilhelm wundt became the first person that implement scientific method in analyzing the pyschological phenomenon.

due to this result, wilhelm wundt also able to make psychology to be acknowledged as a separate scientific field from biology.

they had freedom from the government and from the affairs