 abstract objects |  Aristotle |  categories |  causation: the metaphysics of |  consciousness |  epiphenomenalism |  existence |  form vs. matter |  identity: of indiscernibles |  intentionality |  laws of nature |  Leibniz, Gottfried Wilhelm: modal metaphysics |  logic: classical |  mass expressions: metaphysics of |  material constitution |  mereology |  metaphysics |  monism |  Moore, George Edward |  natural kinds |  nominalism: in metaphysics |  nonexistent objects |  ontological commitment |  ordinary objects |  perception: the contents of |  physicalism |  Platonism: in metaphysics |  plural quantification |  possible objects |  properties |  propositions |  quantifiers and quantification |  Quine, Willard Van Orman |  reference |  relations |  Russell, Bertrand |  Strawson, Peter Frederick |  substance |  temporal parts |  tropes |  truth |  truth: correspondence theory of 