Sedevacantism

Sedevacantism is the position, held by a minority of traditionalist Catholics, that the alleged present occupant of the Holy See is not truly pope due to the mainstream church's espousal of the heresy of modernism and that, for lack of a valid pope, the see has been vacant since the death of Pope Pius XII in 1958.

The term "sedevacantism" is derived from the Latin phrase sede vacante, which literally means "with the chair [of St. Peter] vacant". The phrase is commonly used to refer specifically to a vacancy of the Holy See from the death or resignation of a pope to the election of his successor. "Sedevacantism" as a term in English appears to date from the 1980s, though the movement itself is older.

Among those who maintain that the see of Rome, occupied by what they declare to be an illegitimate pope, was really vacant, some have chosen an alternative pope of their own, and thus in their view ended the vacancy of the see, and are known sometimes as "conclavists".

The number of sedevacantists is largely unknown, with estimates given in tens to hundreds of thousands.

Sedevacantism owes its origins to the rejection of the theological and disciplinary changes implemented following the Second Vatican Council (1962–65). Sedevacantists reject this Council, on the basis of their interpretation of its documents on ecumenism and religious liberty, among others, which they see as contradicting the traditional teachings of the Catholic Church and as denying the unique mission of Catholicism as the one true religion, outside of which there is no salvation. They also say that new disciplinary norms, such as the Mass of Paul VI, promulgated on 3 April 1969, undermine or conflict with the historical Catholic faith and are deemed heresies. They conclude, on the basis of their rejection of the revised Mass rite and of postconciliar Church teaching as false, that the popes involved are false also.

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