 The Formula of Concord closed the controversy by avoiding both extremes, but failed to offer a final solution of the question demanded by the original motive of the controversy.The synergistic controversy, breaking out about the same time, also sprang out of the ethical interest which had induced Melanchthon to enunciate the doctrine of free will in opposition to his previous predestinarianism.After the clash in 1555 between Pfeffinger (who in his "Propositiones de libero arbitrio" had held closely to the formula of Melanchthon) and Amsdorf and Flacius, Strigel went deeper into the matter in 1559 and insisted that grace worked upon sinful men as upon personalities, not natural objects without a will; and that in the position that there was a spontaneous cooperation of human powers released by grace there was an actual lapse into the Roman Catholic view.