Realism is 'a sober philosophy' which holds that there is an objective, outer world. Although it takes different forms, realists assert that our statements about the world can be true or false, depending on whether they match what is really 'out there'. The idea was challenged vociferously in the 20th Century and beyond. From Wittgenstein to Derrida, many philosophers have argued that this account of our relationship to the world is simply impossible. Here, three contemporary philosophers approach this question from their own perspectives, taking on each other's ideas and bringing out new contradictions and challenges in the fundamental nature of our relationship to the world.