 Furthermore, making an assertion commits you to respond to people’s questions and challenges in certain ways, as the conversation evolves. Brandom (1994: 173–175) emphasizes this, and argues that asserting achieves two different social results at the same time: (i) it commits the speaker to defend her claim in response to legitimate challenges; and relatedly (ii) authorizes the hearer to claim anything that follows from what the speaker asserted. MacFarlane (2003: 14  [Other Internet References])  summarizes (and revises) the underlying idea as follows: