At the age of 62, 08-December-1854 : Pope Pius IX in the Papal Bull ''Ineffabilis Deus'' defines ''ex Cathedra'' the dogma of Immaculate Conception, which holds that the Blessed Virgin Mary was conceived without original sin.
At the age of 72, 08-December-1864 : ''Syllabus errorum'': Pope Pius IX condemns theological liberalism as an error and claims for the supremacy of Roman Catholic Church authority over the civil society. He also condemns rationalism and socialism.
At the age of 78, 18-July-1870 : ''Pastor Aeternus'': Pope Pius IX declares papal infallibility in matters of faith and morals.