I thought MBTI tests give you your 4 letter personality code as well as where you fall on the spectrum for each letter. For example, someone who has a 5% bias towards introversion will be very different than someone with a 85% bias towards introversion even if the other 3 letters and their corresponding degrees of bias were held fixed. Similarly, that person with a 5% bias towards introversion is closer in personality to someone with a 5% bias towards extroversion but with the other 3 dimensions held fixed even though their personality codes are different.

Any personality typing system that categorizes ppl into 16 boxes is too limiting. However, MBTI, in its true spirit, projects everyone’s personalities as a point in 4D space (or 5D if you include assertiveness/turbulence). Yes, there are probably more than 4-5 different traits or dimensions contributing to one’s personality but investigating them all would make any personality typing system too complex for any practical use. As per the 80/20 rule, we only investigate the few personality traits that contribute the most to one’s overall personality, although different systems like MBTI and Big 5 differ on what they think are the key personality traits.