In 2011 the Prime Minister of the UK David Cameron during a Commons debate told the then shadow Chief Secretary to the Treasury Angela Eagle to "calm down, dear". His words were widely taken to be sexist, patronising and arrogant. They betrayed a fairly transparent attempt to rely on stereotypes about women's judgement being clouded by emotion in order to undermine or deflate the credibility of her questioning of his policies. 1 They also were an attempt to silence her. Cameron did not intend literally to prevent her from speaking by physically closing her mouth or by interrupting her, although he may have done the latter. Rather, he wanted her attempts to describe what she saw as the failures of his policies, not to have, in the eyes of the other present members of the Commons, the status of assertions. He attempted to achieve this by feigning that he had not recognised her intentions. By saying to her to calm down, he was insinuating that because of her emotional state it was impossible to surmise what she may be saying. He was telling their audience that her speech did not constitute an input to rational debate because her intentions could not be recognised. His gambit did not pay off, as it was transparently disingenuous, but it was an attempt to silence his opponent by causing her assertions to misfire. 2 Intellectual arrogance is a very common and varied phenomenon. The fairly recent episode mentioned above is only one example; but arrogance is encountered in all walks of life. 3 It is exhibited by individuals who do not respect their turn in conversation, who interrupt others, who take up an unfair share of the available time. It shows up when a person boasts about his achievements, never admits to a mistake, publicly puts other 1 On deflating credibility as a kind of testimonial injustice see, Miranda Fricker's ground-breaking Epistemic Injustice (2007). 2 As a matter of fact the gambit backfired because it was widely interpreted as indicating an inability to remain cool under pressure. By telling Eagle to calm down, Cameron had shown that he was flustered and unable to address the content of her challenge. I shall explain the nature of illocutionary disablement or silencing by causing a speech act to misfire below. For reporting of this episode see http://www.theguardian.com/ politics/2011/apr/27/david-cameron-calm-down-dear [accessed on 30 July 2015]. The locus classicus on illocutionary silence is Rae Langton (1993) see also her (2009). 3 For reasons of brevity in the rest of this paper I use 'arrogance' as a shorthand for 'intellectual arrogance'. Whenever arrogance in general is intended, this fact is indicated explicitly.2 people "in their place", or thinks that he is always right. 4 It is also manifested by excessive risk takers, by people who do not tolerate dissent, by those who try to intimidate others into agreeing with them.Despite its prevalence intellectual arrogance has not received the detailed philosophical attention that it deserves. To my knowledge very little has been written in r...