Since 2011, Ralf Busse has been professor of philosophy at Johannes Gutenberg University Mainz. In his research, he focuses on metaphysics and ontology, philosophy of language, logics, epistemology and philosophy of science. As GRC fellow, he intends to finish his monography on "categorial metaphysics", in which he brings together logics and semantics, philosophy of science and metaphysics. By reflecting on methodological questions of so called metametaphysics, he gains critical and constructive insights for core debates of current analytic metaphysics.