On the question of cognitive limits in diagnostic histopathology

From a solely morphological point of view, histopathological diagnosis is subject to interpretation variables that may be investigated from an epistemological aspect. On the basis of the most suitable ways of approach, the authors examine some theoretical aspects involved in writing a histopathological report. In particular, the following are considered: problems regarding the perception of shapes, induction, deduction, abduction and some aspects of formal logic connected with the evaluation of immunohistochemical investigations. The main reasons for diagnostic mistakes are underlined, and the opportunity for an awareness of the logical and mental mechanisms involved in the evaluation of morphological data is outlined.