A Short Battery of Simple Tests for Measuring Overinclusive Thinking

Abstract

Overinclusive thinking has been regarded by some authorities as an important aspect of the thought disorder found in schizophrenic patients (8). Norman Cameron (2, 3, 4, 5), who performed the pioneer studies in this field, defined overinclusive thinking as the inability to preserve conceptual boundaries, as a result of which distantly associated and even irrelevant ideas come to be regarded as essential parts of a concept. This abnormality necessarily makes thought more abstract and less precise. Furthermore, it can lead to overlapping concepts which share elements in common, when, normally, they should be mutually exclusive, a situation which allows the thought-disordered person to entertain two mutually incompatible ideas at the same time without recognizing the contradiction.