n 1942, a mother-daughter duo named Katherine Cook Briggs and Isabel Briggs Myers developed a questionnaire that classified people’s personalities into 16 types. Called the Myers-Briggs Type Indicator, or MBTI, it would go on to become one of the world’s most widely-used personality tests. But do these tests actually reveal truths about personality? Merve Emre examines their design flaws. Lesson by Merve Emre, directed by Seoro Oh.