Formal consistency statement (source code)

= Formal consistency statement
{title2=$\operatorname{Con}(T)$}

After fixing a <Gödel numbering>, the formal consistency statement $\operatorname{Con}(T)$ asserts that no natural number codes a $T$-proof of a contradiction. For a recursively axiomatized theory, this is an arithmetical sentence expressible inside any sufficiently strong base theory.