That laughter invites laughter is a basic tenet of Conversation Analysis analyses of laughter, whereas emotion psychology analyses describe various emotive and social effects laughter exhibits relative to various phonetic parameters. We provide data concerning laughter responses to laughter which we argue show neither approach can explicate and more generally suggest they cannot offer a general account of laughter and related non-verbal social signals. We sketch how distinct kinds of laughter responses to laughter - along with a host of other kinds of responses - can be systematically analyzed within a dialogical semantics, which integrates illocutionary and emotive effects.