The Language of Atoms argues that ancient Epicurean writing on language offers a theory of performative language. Such a theory describes how languages acts, providing psychic therapy or creating new verbal meanings, rather than passively describing the nature of the universe. This observation allows us new insight into how Lucretius, our primary surviving Epicurean author, uses language in his great poem, De rerum natura (On the Nature of Things). The book begins with a double contention: on the one hand, while scholarship on Lucretius has looked to connect Lucretius' text to its larger cultural and historical context, it has never turned to speech act theory in this quest. This omission is striking at least in so far as speech act theory was developed precisely as a way of locating language (including texts) within a theory of action. The book studies Lucretius' work in the light of performative language, looking at promising, acts of naming, and the larger political implications of these linguistic acts. The Language of Atoms locates itself at the intersection of both older scholarly work on Epicureanism and recent developments on the reception history, and will thus offer scholars across the humanities a challenging new perspective on Lucretius' work.