Page:Mary Whiton Calkins - Kant's Conception of the Leibniz Space and Time Doctrine (The Philosophical Review, 1897-07-01).pdf/3

Rh In his more detailed discussion of extension, Leibniz seems in fact to treat it much as many modern psychologists treat space-sensations. For, in the first place, he often calls extension phenomenal or phenomenon. “Extensionem et resistentiam aut phenomena,” he says in one place. “Extensio non nisi phenomenon,” is another such expression. More definitely, as in the quotation already made from the Principes de Malebranche, extension (like duration) is called an attribute of things. In the description of the nature of this attribute, we encounter some difficulties of interpretation. Leibniz insists that extension and duration are abstract attributes, that is, that there exists no merely extended thing, nothing with the single quality of extension. Or, as he expresses himself in a slightly different form, extension always supposes something which is extended. The exact words are: “Extension is none other than an abstraction (un abstrait) … and requires something which shall be extended. It needs, as duration does, a subject. It even supposes the subject to have a certain sort of antecedence; some quality which is extended, is spread out (qui s'étende, se répande).” By the ‘subject’ of the extension Leibniz seems to refer to what later in the same paragraph he calls antitypte or la matérialité, that is, resistance or impenetrability. For much of Leibniz’s discussion of extension is a criticism and refutation of Descartes’ doctrine of the identity of matter with extension; and he always insists that matter requires more than extension, that is, antitypia or passive resistance.

But the most tangible and definite part of this statement is that which virtually points out that extension is one of several qualities of a thing, an accompaniment of some other antecedent quality. As expressing this condition of extension, the word ‘diffusion’ becomes for Leibniz a favorite synonym; one can hardly call it a definition. The qualities with which extension is combined are visual or tactual. ”For example, in milk there is an extension or diffusion of whiteness; in the