An original metaphysical proposal building on classical and contemporary sources. In Centering and Extending, Steven G. Smith retrieves and refashions some of the best ideas of classical and early modern metaphysics to support insight into the natures of mental and material beings and their relations. Avoiding what he critiques as distortive paths of idealism, materialism, repressive monism, and overly permissive pluralism, Smith builds his framework on centering and extending as universal principles of formation. Identifying the basic consistency of being with these principles in symmetrical partnership enables a naturalist process view that, unlike Whitehead's, does not overbalance toward the subjective and teleological and, unlike Deleuze and Guattari's, does not overbalance toward the material and chaotic. This view supports useful conceptions of mind and matter, form and energy, reason and cause, and a layered world order without relying on a blind concept of supervenience or emergence. It also respects and reinforces a division of roles between metaphysical sense-making and spiritual determinations of meaningfulness.