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|Berka I 18/19
Making true/Thruthmaker/premises/consequences/conclusions/Bolzano: The assumption that all the representations that make the sentencecs A, B, C ... (premises) true in the place of i, j, ..., also make the conclusions M, N, O ... true, does not even presuppose that this must be the other way round.
Derivability/Bolzano: is not symmetrical.
N.B.: the premises do not make the conclusions true, but there is a third, the ideas which make the conclusions true and also the premises.
For example, a pair of ideas that makes true, for example, "all a are b" also makes true at the same time: "some a are b" but not vice versa.
K. Berka/L. Kreiser
Logik Texte Berlin 1983