a career counsellor told them to work through an “instrument” – decidedly not a “test” – called the Myers-Briggs Type Indicator. The MBTI is the world’s dominant personality questionnaire: more than 50 million people around the globe are estimated to have taken it. It has been administered since the 1940s (though its origins date to 1917) and now consists of 93 questions to which you answer A or B. At the end, you are assigned one of 16 different types. Many consider this “score” to be meaningless, no more scientifically valid than your star sign. But others – including companies such as Bain, the BBC and many universities – clearly do not.

No one type is better than another. The creators of the MBTI – two American women, Katharine Cook Briggs and her daughter, Isabel Briggs Myers – imagined it as primarily a tool for self-discovery. But that doesn’t mean all types are equal.

Comments under the article:
It is not, as some commenters have suggested, that psychology and psychological testing is “half baked.” It is that everyone is an expert at functional psychology at some level already — one has to be to live in a social world — just not an expert at the science of psychology; and it seems, to the lay-person, that psychological testing tools are pretty obvious and should be usable by anyone.