The Mormon Mirror
When a JW dismisses Mormon claims as obviously wrong, they have already applied the test that disproves their own organisation. Both groups emerged from the 19th-century American restorationist milieu of upstate New York's "Burned-over District" — Mormonism in the 1820s-30s, the Bible Students in the 1870s. Both are restorationist (claiming the true church had vanished from the earth until their founder appeared), millenarian (organised around an imminent climactic intervention by God), and non-trinitarian. Both claim to be the sole restored true church. Both add an extrabiblical authority above Scripture (the Book of Mormon / the Watchtower). Both have a prophetic founder followed by a consolidating successor (Smith → Young, Russell → Rutherford). Both teach a two-tier salvation in which only an elite enter the highest state. Both have repeatedly altered teachings the founder presented as divine revelation. Both treat departure with total social exclusion (shunning/disfellowshipping) to protect the group's purity. The Mormon comparison is the most powerful "outside view" mirror a JW can be invited to look into — because the JW already agrees that Mormon claims are unconvincing.