|General validity: within a calculus a formula that is satisfied by any interpretation (variable assignment with expressions for objects) is valid. See also satisfaction, satisfiability, interpretation.|
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|Validity||P. Lorenzen Ein dialogisches Konstruktivitätskriterium (1959) in Karel Berka/L. Kreiser Logik Texte Berlin, 1983
Berka I 268
Definition logical validity/dialogical logic/Lorenzen: validity consists in the existence of a strategy for the proponent P, in which he only has to claim prime formulas which have been previously claimed by O. Then the tableau is closed.
Constructive Philosophy Cambridge 1987
K. Berka/L. Kreiser
Logik Texte Berlin 1983