hereby :: thesis: ( ( for x being Nat holds GSq . x is _trivial ) implies GSq is _trivial )
assume A1: GSq is _trivial ; :: thesis: for x being Nat holds GSq . x is _trivial
let x be Nat; :: thesis: GSq . x is _trivial
x in dom GSq by LmNat;
hence GSq . x is _trivial by A1; :: thesis: verum
end;
assume A2: for x being Nat holds GSq . x is _trivial ; :: thesis: GSq is _trivial
let x be Element of dom GSq; :: according to GLIB_000:def 68 :: thesis: GSq . x is _trivial
thus GSq . x is _trivial by A2; :: thesis: verum