True or False Pope?

True or False Pope? Refuting Sedevacantism and Other Modern Errors is a book by John Salza and Robert Siscoe, first published in 2015, together with a companion website at trueorfalsepope.com. The paperback runs to roughly 700 pages; listings variously give the publisher as St. Thomas Aquinas Seminary or an independent publisher, and a Kindle edition followed in 2022 (Amazon; Google Books; Amazon Kindle). It carries a foreword by Bernard Fellay, then superior general of the Society of St. Pius X, who wrote that only articles and booklets had previously been published against sedevacantism in English (SSPX.org).

Argument. According to an SSPX review, the book argues that sedevacantism logically leads to denying the Church's attributes (visibility, indefectibility, infallibility) and marks, especially apostolicity, and that sedevacantists misread their favoured authorities, especially St. Robert Bellarmine (SSPX.org; FSSPX Asia). Endorsements on the book's website, which are promotional, include Fr. Brian Harrison and Christopher Ferrara; Harrison described the authors as avowed traditionalists who criticise the revised liturgy and certain Vatican II teachings (True or False Pope?). The book has become a reference text for traditionalists who recognise the post-conciliar popes while criticising aspects of the reforms (see recognize-and-resist); its authors later applied similar arguments against claims associated with benevacantism.

Debate. The authors debated the sedevacantist priest Anthony Cekada and others in The Remnant (The Remnant) and answered Paul Kramer's arguments against the papacy of Francis (The Remnant). The book was promoted by SSPX outlets and discussed on Catholicism.org (Catholicism.org). The current posting frequency of the companion website was not verified.