Add to ORKGThe publication of Bruno Latour’s last book An Inquiry into Modes of Existence is an important step in the author’s intellectual evolution, as he presents himself as a responsible metaphysicist. Yet, if this attitude might be praised by some intellectuals, it raises methodological and epistemological questions. This article deals with the implications of this « methaphysical turn » on the way sociology is defined and practiced. Three levels are taken into account. First, we shall ask what, in Bruno Latour’s style or manner, makes discussion awkward. Second, we shall scrutinize which are the difficulties to link « radical empiricism » and « ontological pluralism » without a theory of language. Third, we shall make some observations regarding...