In both the historical and contemporary literature on the metaphysics of space, a core dispute is that between relationism and substantivalism. One version of the latter is supersubstantivalism, according to which space is the only kind of substance, such that what we think of as individual material objects are actually just parts of spacetime which instantiate certain properties. If those parts are ontologically dependent on spacetime as a whole, then we arrive at an ontology with only a single genuinely independent (...) substance, namely the entire spacetime manifold. This is monist supersubstantivalism. A view on which the parts of spacetime are ontologically prior to the whole has been called pluralistic supersubstantivalism. As currently formulated, supersubstantivalism carries significant advantages and encounters major difficulties. I argue that some of the latter motivate... (shrink)