Being an art buyer these days is comprehensively and indisputably vulgar. It is the sport of the Eurotrashy, Hedge-fundy, Hamptonites; of trendy oligarchs and oiligarchs; and of art dealers with masturbatory levels of self-regard.

If I stop being on good behaviour for a moment, my dark little secret is that I don't actually believe many people in the art world have much feeling for art and simply cannot tell a good artist from a weak one, until the artist has enjoyed the validation of others - a received pronunciation.

Few people in contemporary art demonstrate much curiosity. The majority spend their days blathering on, rather than trying to work out why one artist is more interesting than another, or why one picture works and another doesn't.

There are no rules about investment. Sharks can be good. Artist's dung can be good. Oil on canvas can be good.

Nobody can give you advice after you've been collecting for a while. If you don't enjoy making your own decisions, you're never going to be much of a collector anyway.

Many people cycle or swim to keep trim. But if swimming is so good for the figure, how do you explain whales?

Being a good artist is the toughest job you could pick, and you have to be a little nuts to take it on.