Of all the outrages of contemporary political life perhaps the greatest is the apparent disregard for truth, for which we have the new coinage, 'posttruth'. What can we use to oppose this tendency? Facts? That's something photographs should be able to help us with. But are facts the same as the truth? And are photographs a way to provide them? David Bate disentangles this confusing subject with the help of an anteater and a shelf of china.