  The most detailed and influential response to the argument from theory change is due to Psillos (1999), who combines strategies (I) and (II). Hasok Chang (2003), Kyle Stanford (2002 and 2003), Mohammed Elsamahi (2005) and Timothy Lyons (2006) criticize Psillos's account. Other responses include Kitcher's (1993) model of reference according to which some tokens of theoretical terms refer and others do not. Christina McLeish (2005) criticizes Kitcher's theory by arguing that there are no satisfactory grounds for making the distinction between referring and non-referring tokens. McLeish (2006) argues that abandoned theoretical terms like ‘ether’ partially refer and partially fail to refer. Juha Saatsi (2005) denies premise (a) and claims that there can be approximate truth of the causal roles postulated by a scientific theory without its central terms necessarily successfully referring (see also Chakravartty, 1998).