The early history of the controversy must be pieced together from about 35 documents found in various sources. The Trinitarian historian Socrates of Constantinople reports that Arius first became controversial under the bishop Alexander of Alexandria, when Arius formulated the following syllogism: "If the Father begat the Son, he that was begotten had a beginning of existence: hence it is that there was when the Son was not. It follows then of necessity that he had his existence from the non-existence".