"No hay manera de escapar a la filosofía […] Quien rechaza la filosofía profesa también una filosofía pero sin ser consciente de ella." Karl Jaspers, filósofo y psiquiatra. "There is no escape from philosophy. Anyone who rejects philosophy is himself unconsciously practising a philosophy." [Karl Jaspers, Way to Wisdom 12 (New Haven: Yale University Press, 1951)]
In the minds of most philosophers with a passing familiarity with early-modern philosophy, occasionalism is invariably regarded as a laughable ad hoc or ‘for want of anything better’ alternative to substance dualism as a solution to the mind-body problem that first opened up in Descartes’ Meditations of 1641. As typically presented in philosophy textbooks, the doctrine (usually identified exclusively with Nicholas Malebranche) certainly seems laughable: beginning from the assumption that the actual transmission ofanything between body and mind is impossible, occasionalism holds that, for example, when my finger is pricked by a needle, no physical effect—neither the puncture of the needle nor the activity of my nerves—reaches my mind, but rather God directly produces the sensation of the prick within my mind on theoccasion of the needle’s contact with my finger. Similarly, when I will to retract my finger away from the needle, my incorporeal will is utterly impotent to produce any such corporeal movement, so God again intercedes and directly produces the movement of the finger on the occasion of my willing.
Such supposedly was the doctrine of occasionalism, which, when presented in such a manner, occasions little more than an eye-roll from modern readers. Yet, this “textbook view” of occasionalism (much like the contemporary fixation on Descartes’ Meditations over his Principles of Philosophy) has everything to do with the interests, problems, and concerns of philosophy in the late and post-modern periods, and almost nothing to do with the actual doctrine of occasionalism in its own historical context. Indeed, occasionalism is not peculiar to early-modern philosophy or Cartesianism at all, but was an influential school in both Latin and Islamic medieval philosophy extending back to the tenth century. Moreover, for a strange and systematically theological system of metaphysics, occasionalism is the progenitor of a number of remarkable developments in Western philosophy, some of which laid the foundation for the development of modern science itself.