Art Basel has opened in Switzerland. The show boasts a record number of exhibits across the contemporary art world – more than 2,500 of them in total.Until recently, prices for this kind of art were astronomical, even for relatively unknown artists. But since the financial crisis began, prices have fallen to more reasonable levels leading specialists to estimate that the speculative price bubble amongst art collectors has burst. Happily, in the art world there are still people who buy works for their own sake, because they love them. And for these buyers, the value of their purchases is always inestimable. The Thyssen Museum in Madrid is exhibiting 74 paintings, sculptures and drawings by Matisse. This exhibition, Matisse 1917 to 1941, covers works from the middle period of his career, which are perhaps less well known than those from his later years. The exhibition runs until 20th September.