Will, Existence, Actuality

'Existence' seems equivocal for Spinoza, e. g. both an undrawn rectangle that is inscribed in a circle and a drawn one 'exist' in his system. Now, since each of those types of rectangle possesses extension, the latter cannot be the criterion of the distinction between the two. Instead, one way of characterization the difference is as 'virtual' vs. 'actual', given that Spinoza often uses the latter in reference to living Modes, to contrast them with their immortal essences, which are in God in the way a virtual rectangle is implicit in a circle. However, seemingly still lacking in Spinoza's system is an account of the process of actualization, e. g. 'causality' is insufficient, since it applies to virtual essences as well to actual things. In contrast, here, the nature of the process of actualization is clear from Spinoza's own genetic definition of a Circle--a combination of Will, i. e. indeterminate Motility, and structuring in accordance with the terms of the definition. Given Spinoza's recognition of virtual Extension, it is difficult to project into his system any analogously decisive notion of 'actualization'.