ABSTRACT
The specification of matter as a voluminous substance – as a substance 3-dimensionally extended in physical space – is itself, one may suppose, to some degree topic-specific. Moreover, on the face of it, it seems that the topic-specificity is enough to exclude a mentalistic interpretation. The most obvious thing we can specify about the intrinsic nature of physical space is its geometrical structure. For, in giving a purely geometrical account of gravitational fields, the General Theory postulates a 4-dimensional space-time continuum whose curvature varies from region to region with the varying density of matter. One way, the particles are ontologically constituted as occupants of the space. The other way, the space is ontologically constituted as a medium for the particles. For if particles are ontologically constituted as occupants of physical space, it follows automatically that, for them, the occupancy of space is an essential attribute.
