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Paradox of implication / solution / Armstrong: univesale uantifikation: says something about every thing: even if there is no Q: "either there or it is not an F that is a G (> empty description) - problem: the term of a positive antecedent syntactically difficult to define - nevertheless "be a centaur": semantically and syntactically clear.
AR II = Disp
D. M. Armstrong
Dispositions, Tim Crane, London New York 1996
What is a Law of Nature? Cambridge 1983