||Social externalism claims that the meaning of a representational item is constitutively (rather than merely causally) determined partly by social factors. For example, social externalism claims that the meaning of a word in my mouth is determined partly by how others use that word, rather than solely by how I use that word or conceive of its meaning. Social externalism raises many questions about the nature and generation of meaning. To what degree is meaning determined socially? What types of representations have their meaning determined socially? What is the social and what is its role in determining meaning? Is social externalism really distinct from more general types of semantic externalism? Can we divide the determinants of meaning into social and non-social factors? Can we incompletely understand, or even misunderstand, the meanings of our own representations?