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INDIVIDUALS/Meixner: individual-like objects: e.g. round the square but also e.g. Holmes, fictional people and their body parts, which cannot be said to have certain properties or not to have them. - The man who knew that he knows nothing: not Socrates, but an INDIVIDUAL. (overdetermined: knowledge / ignorance).
Def overdetermination: anything is overdetermined if there is at least one property that can be claimed by: x has f and not-f.
Einführung in die Ontologie Darmstadt 2004