The Rorschach ink blot test is one of the most popular and controversial personality tests used by psychologists here and abroad. The theory is that we reveal our true selves through interpreting ambiguous shapes. It was developed nearly a century ago by the Swiss psychiatrist Hermann Rorschach - a man who worked outside the mainstream and who died young.
Jo Fidgen traces the origins, refinement and application of Rorschach's test and its subsequent falling from favour. She visits the Tavistock Centre in London, where it is still in clinical use, and the Hermann Rorschach Museum and Archives in Bern, Switzerland. She also talks to psychologists around the world - in Japan, where it's more popular than ever, and in the US where controversy rages about its reliability and validity. And she undertakes the test herself.
With contributions from Dr Michael Drayton, Dr Justine McCarthy-Woods, Dr Noriko Nakamura, Dr Scott Lilienfeld, Dr Bruce Smith, Professor Anne Andronikof and Rita Signer, curator of the Rorschach Archives.
Produced by Alan Hall
A Falling Tree production for BBC Radio 4.