Weak negation

In positivism and formal logic, positivism takes place in the weak negation (English: Negation as Failure). Theorem is that if an atomic expression can not be proved by resolution, the expression is generally assumed to be false. The weak negation is also used in the programming language PROLOG.

Pseudocode:

if (¬resolute (goal p)), then (assert ¬p)

The weak negation is meaningful, since it must be assumed that the collected knowledge is always incomplete and the resolution can therefore often not give clear results. Edit sample source text

In Horn clause form: heating_defekt: - ¬batterie_leer, heat blower_defekt

If battery_leer can not be found to be true by resolution, it is assumed that battery_leer is not valid. Thus, heating_defect is true when heat fan_defect is true. Edit sourcetext

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