Body and Mind. The Logic of now-now in the Philosophy of Spinoza

According to Ethics, II, 21, scholium: « mind and body, are one and the same individual (individuum) conceived now under the attribute of thought, now under the attribute of extension ». The conception of the individual is thus governed by what could be called a logic of alternation, a logic of now-now, which invites us to understand things, in turn, from the attribute of extension or from the attribute of thought. As a matter of fact, in the history of Spinozism, this logic of alternation was often left aside, and replaced by a logic of correspondence or correlation, more widely known under the vague name of parallelism. Without contesting the logic of correspondence, the logic of alternation is nevertheless characterized by a specificity which has to be analysed. The possibility to conceive a thing now under the attribute of extension, now under the attribute of thought, invites us to investigate indeed the reasons for the change of attribute and for the switch from one attribute to the other. Unlike the parallelist model, it does not a priori exclude some dissymetries which entail that it might be easier on certain occasions to understand the individual by refering to the attribute of thought rather than to the attribute of extension, or the other way round. It also suggests that it is possible to give a full account of a thing, without trying to know at the same time what its equivalent could be in the other attribute. That is why it is necessary, in order to understand the nature of alternation and the reasons for its existence, to examine this intermittent logic of now-now.