Madness is probably as old as the human race. Archaeologists have discovered skulls dating back at least to 3000 BC which have been trephined - small round holes have been bored in them with flint tools.

The likeliest explanation is that the person was thought to be possessed by devils - we would say they were mad or epileptic - and that the holes were to allow the demons to escape. In early times madness was usually interpreted as the work of evil spirits.

Amongst the Greeks, you were told to keep well away from crazy people in case the demons leapt out from them and got you too. And Christians thought the same. Madness might be the work of the Devil; Satan possessed his victims and caused them to run wild, to talk nonsense or to blaspheme, swearing and cursing.

Yet the Christian religion also brought another and more positive view. Madness might be a sort of divine experience, a holy innocence. Prophets and visionaries had a 'good madness' unlike the 'bad madness' that came from Lucifer.

There were other sorts of 'good madness' too. Poets and painters were often called mad on account of their indifference to worldly things like money and because of the power of their imagination, seeing things that others couldn't. Genius and madness went together, it was always said.

That view was applied to the Romantics in the nineteenth century, and more recently to rock singers.

There have been breakthroughs recently. Better drug treatments have come about; brain scans can sometimes see the abnormalities in the brains of schizophrenics.

But people with psychiatric disorders are still feared, misunderstood and neglected, and with the closing down of many psychiatric hospitals they have often joined the ranks of the homeless and hungry.

William Hogarth's A Rake's Progress

Published in 1735. The scene shown here is set in Bethlem Hospital. Reproduced courtesy of Bethel Royal Hospital Archive and Museum