 
Summary: A Proof Assistant for a WeaklyTyped
Higher Order Logic

Jamie Andrews

Department of Computer Science, University of
Western Ontario
In previous ALP newsletters, readers have read ar
ticles that describe several theorem proving systems
for higher order logic [Pfe01, Fel02, Pie03]. This arti
cle does the same, but for a higher order logic with a
weaker type system than classic higher order logics.
The logic in question is referred to as G, which stands
for Gilmore; it is inspired by similar logics developed
by P. C. Gilmore [Gil97]. Whereas most higher or
der logics maintain consistency by assigning a type
to every term, Gilmore logics maintain consistency
by making a distinction between uses and mentions
of variables standing for properties. A full description
of G can be found in [And02].
