Joseph Berkovitz, Subjective Probabilties and Instrumentalism
October 25 @ 12:00 pm - 1:00 pm
Professor Berkovitz will be discussing his forthcoming paper, “On de Finetti’s Instrumental Philosophy of Probability” in the IHPST Lounge.
De Finetti is one of the founding fathers of the subjective school of probability, where probabilities are coherent degrees of belief. De Finetti held that probabilities are inherently subjective and he argued that none of the objective interpretations of probability makes sense.
While his theory has been influential in science and philosophy, it has encountered various objections. In particular, it has been argued that de Finetti’s concept of probability is too permissive, licensing degrees of belief that we would normally consider imprudent. Further, de Finetti is commonly conceived as giving an operational, behaviorist definition of degrees of belief and accordingly of probability. Thus, his theory is said to inherit the difficulties embodied in operationalism and behaviorism. De Finetti’s celebrated Dutch book argument for the laws of probability, where it is argued that incoherent degrees of belief could lead to a loss come what may, has also been the subject of various objections.
We argue that these objections overlook central aspects of de Finetti’s philosophy of probability and are largely unfounded. We propose a new interpretation of de Finetti’s theory that highlights these aspects and explains how they are an integral part of de Finetti’s instrumentalist philosophy of probability. We conclude by drawing an analogy between misconceptions about de Finetti’s philosophy of probability and common misconceptions about instrumentalism.