|Existence, philosophy, logic: the fact that there is something to which properties can be attributed. That does not mean that something has to be given immediately or can be perceived by the senses. See also ontology, properties, predicates, existence statements, realism, quantification, ascription.|
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Existence/topicality/ontology/Meixner: it is not conceptually natural that something that exists, really is - it is however vice versa: everything what is real exists, - "there is": unclear - Meixner pro empty categories, pro unrealized possibility as a fact , not individual.
Einführung in die Ontologie Darmstadt 2004