Summary
Overview
Josh and Chuck dive deep into personality tests, focusing primarily on the Myers-Briggs Type Indicator (MBTI). They explore the history of personality classification from ancient humors to modern psychometric instruments, examine how these tests are used in corporate America, and critically analyze the scientific validity and real-world implications of categorizing human personality. The episode reveals significant flaws in popular personality assessments while acknowledging their widespread adoption in hiring, criminal cases, and therapy.
Origins of Personality Classification: From Four Humors to Carl Jung
The hosts trace personality categorization back to ancient times with Hippocrates' four humors (black bile, yellow bile, phlegm, and blood), which were linked to both physical health and personality types like melancholic, choleric, sanguine, and phlegmatic. They explain how Carl Jung's 1921 book 'Psychological Types' established modern personality classification with four categories (sensation, intuition, thinking, and feeling) modified by introversion/extroversion. The fundamental problem identified is that these systems attempt to box complex human personalities into fixed categories when people actually fluctuate between different states.
- Ancient Greeks linked four humors (black bile, yellow bile, phlegm, blood) to both disease and personality types
- Carl Jung created modern personality types in 1921 with four categories: sensation, intuition, thinking, and feeling
- Jung introduced the widely accepted concepts of introversion and extroversion
- Jung's work was based on his philosophical ideas rather than empirical research or data
" If you are a thinking human being who is not in a vegetative state right now, and for all we know at this point in medical science, maybe even if you are in a vegetative state, you're probably thinking, it doesn't seem like anyone I've ever met is just phlegmatic or just choleric or just sanguine or just melancholy. "
" This whole thing that started back with the four humors and continues on to this day in the guise of personality tests is an attempt to take a human personality and say, you're this. You're this one type. This is your type. This is what you're like, right? And the human personality is just too complex, too squishy, too jelly-like to be boxed into one thing like that. "
The Myers-Briggs Type Indicator: Corporate America's Favorite Test
Katherine Cook Briggs and her daughter Isabel Briggs Myers developed the MBTI after World War II to help women entering the workforce find suitable jobs. After encountering Jung's work, Katherine reportedly threw her previous research into the fire to start over based on his theories. The test gained widespread adoption after 1975 when CPP became its publisher, and it's now used by 89% of Fortune 100 companies despite not being based on empirical science. The MBTI categorizes people into 16 types using four dichotomies: Introvert/Extrovert, Sensing/Intuition, Thinking/Feeling, and Judging/Perceiving.
- Katherine Cook Briggs and Isabel Briggs Myers developed the test post-WWII for women entering the workforce
- Legend says Katherine threw her work into fire after discovering Jung's theories and started over from scratch
- The test became ubiquitous after CPP started publishing it in 1975
- 89% of Fortune 100 companies use the Myers-Briggs test
- The MBTI sorts people into 16 personality types based on four dichotomies
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