In this paper I attempt to answer the question: What is interdisciplinary communication? I attempt to answer this question, rather than what some might consider the ontologically prior question—what is interdisciplinarity (ID)?—for two reasons: (1) there is no generally agreed-upon definition of ID; and (2) one’s views regarding interdisciplinary communication have a normative relationship with one’s other views of ID, including one’s views of its very essence. I support these claims with reference to the growing literature on ID, which has (...) a marked tendency to favor the idea that interdisciplinary communication entails some kind of ‘integration’. The literature on ID does not yet include very many philosophers, but we have something valuable to offer in addressing the question of interdisciplinary communication. Playing somewhat fast-and-loose with traditional categories of the subdisciplines of philosophy, I group some philosophers—mostly from the philosophy of science, social–political philosophy, and moral theory—and some non-philosophers together to provide three different, but related, answers to the question of interdisciplinary communication. The groups are as follows: (1) Habermas–Klein, (2) Kuhn–MacIntyre, and (3) Bataille–Lyotard. These groups can also be thought of in terms of the types of answers they give to the question of interdisciplinary communication, especially in terms of the following key words (where the numbers correspond to the groups from the previous sentence): (1) consensus, (2) incommensurability, and (3) invention. (shrink)