Liking and understanding art are two very different things. Because art has the power to polarise and provoke, to entertain and please, to excite, energise and arouse. But it can also exist for its own sake. This is particularly true of contemporary art. Not just paintings, but everything from video and conceptual art to performance and street art, all of which preclude judgement by purely aesthetic criteria. It is exactly this, however, that makes them so exciting to engage with.