The ontology of medicine—the question of whether disease entities are real or not—is an underdeveloped area of philosophical inquiry. This essay explains the primary question at issue in medical ontology, discusses why answering this question is important from both a philosophical and a practical perspective, and argues that the problem of medical ontology is unique, i.e., distinct, from the ontological problems raised by other sciences and therefore requires its own analysis.

The Linda paradox is a key topic in current debates on the rationality of human reasoning and its limitations. We present a novel analysis of this paradox, based on the notion of verisimilitude as studied in the philosophy of science. The comparison with an alternative analysis based on probabilistic confirmation suggests how to overcome some problems of our account by introducing an adequately defined notion of verisimilitudinarian confirmation.