What are Human Beings? Essences an Aptitudes in Spinoza's Anthropology

Spinoza deals with humans and "human essence" but it is not clear how consistent his use of these notions is. The problem evoked by Spinoza's anthropology concerns in turn the status of singular versus general essences and the relationship between those essences and their concrete condition of existence. In this paper, I propose to distinguish between these levels in order to argue that humanity exists insofar as different individuals can agree among themselves and become adapted to each other to live and operate together. Firstly, I examine Spinoza's use of the term "aptus" in order to show that eternal singular essences can exist in different ways according to the extent they can be "adapted" to their environment, that is, to external causes. Secondly, I claim that "human essence" has to be understood as a general essence which therefore results from the "agreements" produced among certain singular essences. Thirdly, I argue that, contrary to the remarkable interpretation provided by Valtteri Viljanen, this ontological picture cannot be explained only by reference to formal causation but needs a genuine kind of efficient causation.