|Ontological Commitment: A theory is bound to the acceptance of objects if it were wrong without the existence of these objects. It may be, however, that parts of the theory do not have to contain the object, then the ontological commitment for the whole theory is omitted. (See H. Lauener Quine, 1982, p. 130).|
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Ontological Commitment / Quine: quantification over non-nominal variables (higher quantification, over properties) nominalised them and thus forces us to believe in corresponding abstract objects.
Objects of thought Oxford 1971
Arthur N. Prior
Papers on Time and Tense 2nd Edition Oxford 2003