Def  b == if b True else False fi

is mentioned by

Thm*  !{p:()| x:. p(x)  prime(x) }

[prime_decider_exists]

In prior sections: bool 1 quot 1 LogicSupplement union rel 1

Try larger context: DiscrMathExt IF YOU CAN SEE THIS go to /sfa/Nuprl/Shared/Xindentation_hack_doc.html