 Whereas the central Maoist line maintained that the masses controlled the means of production through the party's mediation, the ultra-left argued that the objective interests of bureaucrats were structurally determined by the centralist state-form in direct opposition to the objective interests of the masses, regardless of however socialists a given bureaucrat's thought might be.Whereas the central Maoist leaders encouraged the masses to criticize reactionary ideas and habits among the alleged 5% of bad cadres, giving them a chance to "turn over a new leaf" after they had undergone "thought reform", the ultra-left argued that cultural revolution had to give way to political revolution "in which one class overthrows another class".In 1969, French platformist anarcho-communist Daniel Guerin published an essay called "Libertarian Marxism?"