Cheng Jin: He is good at observing people’s behavior and analyzing it, and ultimately achieving the goal of solving cases- it can be regarded as psychoanalysis*
Yang Simo: He has emotional defects and antisocial personality disorder.
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*Psychoanalysis: a system of psychological theory and therapy which aims to treat mental disorders by investigating the interaction of conscious and unconscious elements in the mind and bringing repressed fears and conflicts into the conscious mind by techniques such as dream interpretation and free association.