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|Modalities||Wessel I 347
Modality/Wessel: modality is not a kind of truth value, as often is falsely assumed!
Carnap: identifies truth and logical necessity,
Lukasiewicz: has a third truth value "possible"
Lorenzen: uses "possible" and "possibly true" synonymously. WesselVsLorenzen.
Truth value/Wessel: a truth value is a special logical predicate to which statements are pronounced or denied.
The difference between modalities and truth values is obvious: since alethic modalities are only linked to subjects of the form sA (the fact that A) and truth values are linked only to such with those of the form tA (the statement A) to connect statements.
Truth value: is a statement.
Modality: is a fact.
Constructive Philosophy Cambridge 1987
Logik Berlin 1999