Popes against modern errors : 16 papal documents
	1.	On liberalism (Mirari Vos) by Pope Gregory XVI
	2.	On current errors (Quanta Cura) by Pope Pius IX
	3.	Syllabus of errors by Pope Pius IX
	4.	On government authority (Diuturnum Illud) by Pope Leo XIII
	5.	On Freemasonry and Naturalism (Humanum Genus) by Pope Leo XIII
	⁃	Pope Leo XIII highly recommended Msgr. George F. Dillon's book on this subject: Grand Orient Freemasonry Unmasked (a.k.a War of Anti-Christ with the Church and Christian Civilization)
	⁃	Cf. also The Permanent Instruction of the Alta Vendita by John Vennari
	6.	On the nature of true liberty (Libertas Praestantissimum) by Pope Leo XIII
	7.	On the condition of the working classes (Rerum Novarum) by Pope Leo XIII
	8.	On Christian democracy (Graves de Communi Re) by Pope Leo XIII
	9.	Syllabus condemning the errors of the Modernists (Lamentabili Sane) by Pope St. Pius X
	10.	On Modernism (Pascendi Dominici Gregis) by Pope St. Pius X
	11.	Our Apostolic Mandate (On the "Sillon") by Pope St. Pius X
	12.	The oath against Modernism by Pope St. Pius X
	13.	On the Feast of Christ the King (Quas Primas) by Pope Pius XI
	14.	On fostering true religious unity (Mortalium Animos) by Pope Pius XI
	15.	On atheistic communism (Divini Redemptoris) by Pope Pius XI
	16.	On certain false opinions which threaten to undermine the foundations of Catholic Doctrine (Humani Generis) by Pope Pius XII.
	⁃	Cf. also "The structure of the encyclical 'Humani Generis'" by Reginald Garrigou-Lagrange, O.P., said to be the ghostwriter of "Humani Generis"

The Second Vatican Council (Vatican II)
Vatican II was not infallible because it "ha evitato di pronunciare in modo straordinario dogmi dotati della nota di infallibilità [avoided pronouncing extraordinarily dogmas affected by the note of infallibility]” (Pope Paul VI audience, 12 January 1966) and "In view of conciliar practice and the pastoral purpose of the present Council, this sacred Synod defines matters of faith or morals as binding on the Church only when the Synod itself openly declares so," which it never did (Council's General Secretary, 16 November 1964).