The Centre for Logic and Philosophy of Science of Ghent University was founded in 1993. On occasion of its 20th anniversary the Centre organises an international Conference on Logic and Philosophy of Science (CLPS13) on the themes that are central to its research: Logical analysis of scientific reasoning processes Methodological and epistemological analysis of scientific reasoning processes Keynote talks will be given by Diderik Batens (the founder of the Centre), three logicians (Natacha Alechina, Graham Priest, and Stephen Read), and three philosophers of science (Hanne Andersen, Hasok Chang and Jim Woodward). We welcome submissions for contributed papers on every topic that falls within the scope of the two themes mentioned above. Examples relating to the first topic are: logical analyses of paraconsistent reasoning, reasoning under uncertainty, defeasible reasoning, abduction, causal reasoning, induction, analogical reasoning, belief revision, theory change, conceptual change, erotetic reasoning, argumentation, ... Examples relating to the second topic are: methodological and epistemological analyses of causation and mechanisms, scientific discovery, the structure of scientific theories and models, experiments and thought experiments, theory choice, theory dynamics, rationality, the social organisation of science, expertise, science policy, ....