Some philosophers have recently suggested that the reason mathematics is useful in science is that it expands our expressive capacities. Of these philosophers, only Stephen Yablo has put forward a detailed account of how mathematics brings this advantage. In this article, I set out Yablo's view and argue that it is implausible. Then, I introduce a simpler account and show it is a serious rival to Yablo's. 1) Introduction, 2) Yablo's Expressionism, 3) Psychological Objections to Yablo's Expressionism, 4) Introducing Belief Expressionism, 5) Objections and Replies, 5.1) Yablo's likely response, 5.2) Charity 6 Conclusion. © 2013 The Author 2013.