eqvini-sv

Theorem.

Arguments:

x (sv), y (sv), z (sv),

Assertions:

((xeqy)toexistsz((xeqz)wedge(zeqy)))

Proof:

Hyp Ref Line Expr
ax9-sv1existsz(zeqy)
eqid2(zeqz)
2jct<3((zeqy)to((zeqz)wedge(zeqy)))
3im.bldex4(existsz(zeqy)toexistsz((zeqz)wedge(zeqy)))
1, 4ax-mp5existsz((zeqz)wedge(zeqy))
bv-∀b6(z bound in forallz(zeqx))
ax87((zeqx)to((zeqz)to(xeqz)))
7ax48(forallz(zeqx)to((zeqz)to(xeqz)))
8im.bldan<d9(forallz(zeqx)to(((zeqz)wedge(zeqy))to((xeqz)wedge(zeqy))))
6, 9im.bldexd10(forallz(zeqx)to(existsz((zeqz)wedge(zeqy))toexistsz((xeqz)wedge(zeqy))))
5, 10mpi11(forallz(zeqx)toexistsz((xeqz)wedge(zeqy)))
ax9-sv12existsz(zeqx)
eqcomi13((zeqx)to(xeqz))
2, 13jcti>14((zeqx)to((xeqz)wedge(zeqz)))
14im.bldex15(existsz(zeqx)toexistsz((xeqz)wedge(zeqz)))
12, 15ax-mp16existsz((xeqz)wedge(zeqz))
bv-∀b17(z bound in forallz(zeqy))
ax118((zeqy)to((zeqz)to(zeqy)))
18ax419(forallz(zeqy)to((zeqz)to(zeqy)))
19im.bldan>d20(forallz(zeqy)to(((xeqz)wedge(zeqz))to((xeqz)wedge(zeqy))))
17, 20im.bldexd21(forallz(zeqy)to(existsz((xeqz)wedge(zeqz))toexistsz((xeqz)wedge(zeqy))))
16, 21mpi22(forallz(zeqy)toexistsz((xeqz)wedge(zeqy)))
11, 22jaoi23((forallz(zeqx)veeforallz(zeqy))toexistsz((xeqz)wedge(zeqy)))
23ax124((forallz(zeqx)veeforallz(zeqy))to((xeqy)toexistsz((xeqz)wedge(zeqy))))
nor.an25(lnot(forallz(zeqx)veeforallz(zeqy))leftrightarrow(lnotforallz(zeqx)wedgelnotforallz(zeqy)))
fv-nalx26(z bound in lnotforallz(zeqx))
fv-nalx27(z bound in lnotforallz(zeqy))
26, 27bv-∧28(z bound in (lnotforallz(zeqx)wedgelnotforallz(zeqy)))
ax1229(lnotforallz(zeqx)to(lnotforallz(zeqy)to((xeqy)toforallz(xeqy))))
29imp30((lnotforallz(zeqx)wedgelnotforallz(zeqy))to((xeqy)toforallz(xeqy)))
ax831((xeqz)to((xeqy)to(zeqy)))
31anc2<32((xeqz)to((xeqy)to((xeqz)wedge(zeqy))))
32eqcomi33((zeqx)to((xeqy)to((xeqz)wedge(zeqy))))
28, 30, 33ax4c134((lnotforallz(zeqx)wedgelnotforallz(zeqy))to((xeqy)toexistsz((xeqz)wedge(zeqy))))
25bi>35(lnot(forallz(zeqx)veeforallz(zeqy))to(lnotforallz(zeqx)wedgelnotforallz(zeqy)))
34, 35syl36(lnot(forallz(zeqx)veeforallz(zeqy))to((xeqy)toexistsz((xeqz)wedge(zeqy))))
24, 36casei37((xeqy)toexistsz((xeqz)wedge(zeqy)))