Function dynamics
Function dynamics posits that two individuals of the same psychological type think and behave differently to one another due to how the mental functions within the psyche are functioning. A dysfunctional mental function can result from external stressors which can cause the person to cling to a less conscious function.[1] Jung described such concept as the shadow. Rather than suppressing the unconscious urges Jung believed that they should be slowly integrated into the ego to reduce dysfunction. The dysfunction is but a natural state to alert the user that their psyche requires further development.[2]
For example, an INFJ psychological type is generally loathed to the idea of sex but because sex is a requirement for reproduction and fitness they may feel the uncontrollable urge to act on such impulses during stress. This is the body's mechanism to prompt the INFJ that further development is warranted. Conversely, for the ESTP, they may be drawn to mystical ideas during times of loneliness which is their body's prompt that further attention to the abstract is required. Unfortunately, persons tend to overindulge in the unconscious impulses resulting in maladaptive behaviour or thinking.