Recently I got to talking with a friend about personality assessments, especially in relation to hiring and talent development. It took me awhile to figure out why we were not in agreement: he was thinking about the Myers-Briggs Type Indicator (MBTI) whereas I was thinking about assessments based on the five-factor model (also called the "big five") of personality traits.
Although your Myers-Briggs results can be a fun conversation-starter, they're not based on science but on Carl Jung's fanciful ideas about psychological archetypes. Specifically, the MBTI is not reliable (people get different results depending on when they take it), it's not valid (it's not predictive of behavior and it's not based on a large set of data that's tied to a falsifiable model), it's conceptually muddled (e.g., it claims that thinking and feeling are opposites, but in fact people with good thinking skills also tend to be better at understanding emotions), and it doesn't provide comprehensive insights into its subject-matter (e.g., it doesn't assess key personality traits like emotional stability and conscientiousness).
In other words, it may consist of fascinating speculations, but it's not science.
It's unfortunate that so many people continue to put stock in Myers-Briggs, when we have a scientific model of personality that's based on tons of evidence and solid theory.
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