Experts have found Galen’s theoretical contribution to logic not only interpretively problematic (although see Bobzien 2004), but also ultimately frustrating in its failure both to give a clear and consistent account of itself and to fulfil its ambition systematically to provide what is missing in the pre-existing tradition. What does seem clear is that Galen made a distinctive and in some ways influential and challenging contribution in this area, responding in an original way to both the Aristotelian and the Stoic logical tradition; and that even in the most abstract realm of logical analysis he retained a concern for the practical value of logic and its relatedness to things.