Statement that is claimed to be not true,
propostional logic, denial is often written as "~", as in "~P" i.e. "P
is not true" or "it is not true that P". See
negation for more about the
subtleties involved in saying or writing "not", which is a basic logical
The general logical rule that applies here is that a statement and its denial cannot be both true (at the same time, in the same circumstances).