People love labels. People love boxes, almost as much as cats do. Enter the Myers Briggs personality indicator. The test has around 100 questions and will decide if you’re an extrovert or introvert, thinker or feeler. Your answers will sort you into 1 of 16 personality types. These range from INTJ (the architect) to ESFP (the entertainer). The test has been adapted to help sort people out into many boxes ranging from your Game of Thrones character to your suitability for high ranking jobs.

The test builds upon psychologist Carl Jung’s ideas, who in 1921 theorised that people fit somewhere within 8 categories. Decades later, a mother and daughter team of writers, with no medical training, decided to expand on Jung’s work. From Jung’s 8 types, the number jumped to 16, strictly-fitting people into single categories with little room for any grey area.

However, this multi-million dollar business has been shown to have almost no validity, and no modern researchers in the field of psychology would use such a test for any peer-reviewed research. The test is not consistent since each group is a vaguely described mishmash of attributes, any category could be a reasonable summation of any individual, in a way which is similar to reading your horoscope (known as the Forer effect).

In reality, people are complicated. Sometime in your life you are in one category and sometimes another. But this isn’t new, even Jung knew that personality types were flawed:

“Every individual is an exception to the rule… that this kind of classification is nothing but a childish parlour game”.

So... which ninja turtle character are you?