What is polythetic?

Polythetic is a term commonly used in psychology and cognitive science to describe a classification system where objects or concepts are grouped based on shared characteristics, but not all members of the group share every characteristic. In other words, there is no single defining feature that all members of the group possess, but rather a combination of characteristics that are shared among the members.

Polythetic classification systems are often used in the study of complex concepts or categories that do not have clear-cut boundaries or definitive criteria for inclusion. This approach allows for more flexibility in categorizing and understanding the diversity and variability within a group.

One example of a polythetic classification system is the DSM-5 (Diagnostic and Statistical Manual of Mental Disorders), which is used to diagnose mental health disorders. In this system, different disorders are classified based on a set of criteria that a patient may or may not exhibit, rather than a single defining characteristic.

Overall, polythetic classification systems provide a more nuanced and inclusive way of organizing and understanding diverse concepts and objects, allowing for greater flexibility and complexity in categorization.