 On the other hand, Kenneth Reisman and Patrick Forber (2005) separate the question of whether drift is a force from the question of whether drift is a cause, arguing only for the latter while not taking a stand on the former. In a related paper, they rely on Woodward’s (2003) manipulability account of causation and a 1957 study of drift by Dobzhansky and Pavlovsky to argue that