|Decidability: a question, for example, whether a property applies to an object or not, is decidable if a result can be achieved within a finite time. For this decision process, an algorithm is chosen as a basis. See also halting problem, algorithms, procedures, decision theory.|
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Decidability / tautologies / validity / Mates: for tautologies there a decision process (i.e. to decide whether something is a t.) - not for validity - because for the validity truth wvalue tables are not sufficient - even non-tautological statements can be valid
Decidability / decidable / Mates: is a set of statements if there is a process that decides whether a particular statement is one of them or not - this method need not be known or practicable.
Elementare Logik Göttingen 1969