18 July 1870 July 18, 2016 Author: Staff The First Vatican Council decrees the principle of papal infallibility. Famous Words of Inspiration..."If you are really a product of a materialistic universe, how is it that you don't feel at home there?" C.S. Lewis — Click here for more from C.S. Lewis Related posts: 18 July 1870 1 November 1950 18 September 1870 30 March 1870 28 July 1984 4 July 1569 6 October 1723 18 July 1984 15 June 1752 18 July 1955 Categories: History Tags: 18 July, 1870