Intentionality and Dualism: Does the Idea that Intentionality Is the MOM Necessarily Entail Dualism?

It is well known that Franz Brentano was the first to suggest intentionality, the property of being about something, as a criterion for demarcating the domain of the mental. He suggested that intentionality is a necessary and sufficient condition for something to qualify as a mental event. It is important, for the purposes of this paper, to pay attention to the fact that Brentano’s theory came from within a broader philosophical outlook that was thoroughly dualistic. He sought a total separation of the mental from the physical, and his appeal to intentionality as a defining criterion for the mental is in the service of producing such a separation. In Brentano’s view, only mental events have intentionality, and it is in virtue of this feature that they differ from the events of the physical world. The aim of this paper is to explore whether Brentano’s intentionality criterion for defining the domain of the mental is committed to the broader dualism from which it originated.