Part of learning science is practicing reasoning, but some of the most common approaches to science instruction offer students little opportunity to do that, especially in the whole-class setting of large-enrollment courses. We present and closely examine a single episode of instructor listening--an instructor deliberately adopting a stance, and establishing a classroom culture, in which students' nascent efforts at disciplinary reasoning are elicited, made sense of, and integrated into the collective learning process--in a 140-student introductory chemistry class, as an exemplar of what such instruction can look like. We delineate five aspects of the focal episode that mark it as exemplary of a listening approach to instruction. And we consider concerns about and potential value of such an approach.