 Antoine Arnauld was born in Paris on February 6, 1612, the twentieth and last child of an important French family. He is often referred to in the French literature as Le Grand Arnauld. Another famous member of the family was his sister, Mère Angélique Arnauld. Installed by her wealthy and powerful father as abbess of the convent of Port-Royal in 1602 at the age of eleven, she later reformed the convent and it became a center of intense religious life. Several of Arnauld’s sisters were nuns at Port-Royal, where his mother joined them after the death of his father in 1621.