For instance...

For instance, more motion in a certain respect can produce sensations of heat, less motion produces sensations of cold.[^32] Mentality arises from the interaction between our bodies and the external world, and the idea of the “mind” arises from our second-order experience of ourselves as first-order sensory experiences.

“Because we have now explained what feeling is,” Spinoza says, “we can easily see how from this there arises a reflexive Idea, or knowledge of oneself, experience, and reasoning.”[^33] In the Ethics, he states that mind and body are “one and the same Individual”[^34] and that the mind cannot perceive, imagine, or remember anything without the body: The human Mind does not perceive any external body as actually existing, except through the ideas of the affections of its own Body”[^35] The Mind can neither imagine anything, nor recollect past things, except while the Body endures.[^36] Indeed, Spinoza articulates an inverted image of Sadra’s doctrine that the mind can create the ambient world distinctly belonging to it in arguing that each physical organism generates the mentality fitting to its distinctive physical organization.

From these two very different ways of conceiving experience and embodiment, much else follows. The Lockean emphasis on “solidity” to which Nasr rightly calls our attention was not unconnected with Locke’s notion that God has given matter the power to think without the need for souls. To be sure this suggestion was disturbing to European philosophers in its own time. Descartes did not want to be associated with it, and Leibniz and Berkeley devoted their brilliance to refuting materialism.

Kant did the same. But metaphysics, once having taken on this essentially defensive role in philosophy, was thereafter-and continues to be-haunted by the problem of its own relationship to the world described by science. Spinoza’s philosophy was not, in his mind, a strange hybrid, but an attempt to synthesize some elements of a long-established metaphysics and ethics with Cartesian elements.

Later observers, knowing what came after, seem to be puzzled by the transcendental and unworldly aspects of Spinoza’s philosophy; they see his synthetic project as futile.