Doctrinally, they had disagreements in the beginning; Wasil is said to have converted Amr to his Mu'tazilite opinion in a long discussion. More than Wasil, Amr had belonged to the circle of close disciples around Hasan al-Basri, whose Tafsir he transmitted.
In terms of doctrine, they had initial disagreements; Wasil is said to have convinced Amr of his Mu'tazilite stance during a prolonged conversation. More than Wasil, Amr was part of the group of close disciples surrounding Hasan al-Basri, who taught him Tafsir.