Pluralistic ignorance
Pluralistic ignorance can be contrasted with the false consensus effect. In pluralistic ignorance, people privately disdain but publicly support a norm (or a belief), while the false consensus effect causes people to wrongly assume that most people think like they do, while in reality most people do not think like they do (and express the disagreement openly). For instance, pluralistic ignorance may lead a student to drink alcohol excessively because she believes that everyone else does that, while in reality everyone else also wishes they could avoid binge drinking, but no one expresses that due to the fear of being ostracized. A false consensus for the same situation would mean that the student believes that most other people do not enjoy excessive drinking, while in fact most other people do enjoy that and openly express their opinion about it.
Multitude
Multitude is a term for a group of people who cannot be classed under any other distinct category, except for their shared fact of existence. The term has a history of use reaching back to antiquity, but took on a strictly political concept when it was first used by Machiavelli and reiterated by Spinoza. The multitude is a concept of a population that has not entered into a social contract with a sovereign political body, such that individuals retain the capacity for political self-determination. A multitude typically is classified as a quantity exceeding 100. For Hobbes the multitude was a rabble that needed to enact a social contract with a monarch, thus turning them from a multitude into a people. For Machiavelli and Spinoza both, the role of the multitude vacillates between admiration and contempt. Recently the term has returned to prominence as a new model of resistance against global systems of power as described by political theorists Michael Hardt and Antonio Negri in their international best-seller "Empire" (2000) and expanded upon in their "" (2004). Other theorists recently began to use the term include political thinkers associated with Autonomist Marxism and its sequelae, including Sylvère Lotringer, Paolo Virno, and thinkers connected with the eponymous review "Multitudes".