This article argues that provisional language is important for creating a dialogic space between speakers, where ideas are open for discussion; where participants respect each other's viewpoints; and where the goal is to encourage and explore multiple perspectives. Whilst much of the research on children's talk in the classroom focuses on the language of reasoning (for example, "I think ... because") less attention has been given to the role of more provisional language ("might," "could," "maybe") as students think together. Drawing on previously published research in elementary classes, the article innovatively uses rich examples of children's classroom dialogue to make the case that there is more to idea-sharing than justification and reasoning, and that being "provisional" in language enables a productive and collaborative learning space. The article argues that provisional language deepens and extends a metaphorical dialogic space by enabling creative thinking, epistemic modality and social cohesion.