It takes a madman

I blame Hamlet. It was the Prince of Denmark, or the play that bears his name, that encouraged me to develop a view about human nature which got me into trouble 50 years ago and will, no doubt, do the same today. The idea came to me when preparing for the Certificate of Education (Advanced level) English literature examination, and I was required to address the question: "Was Hamlet mad?"

The conventional theory was based on his various conversations with his father's ghost. When, according to Shakespeare's stage instructions, the spectre appeared on stage, it was reasonable to suppose that the superstitious Elizabethans thought that the "glass of fashion and mould of form" had really returned to haunt his son. All Hamlet's deviant behaviour could, therefore, be attributed to counterfeit lunacy. Once the friendly chats with the "spirit doomed to walk at night" were not preceded in the text by "enter ghost", it was reasonable to assume that Hamlet was suffering from what, these days, is called severe psychological disorder.

To me it seemed there was a better indication of Hamlet's mental state. Although he says not a word, the ghost "enters" (on Shakespeare's instructions) in act 3 scene 4, after line 102. However, Hamlet had gratuitously killed Polonius 90 lines earlier. I concluded when I first read the play, and remain of the view today, that anyone who stabs an old man to death as retribution for no greater sin than being a garrulous humbug is clinically insane - whether or not the ghosts he sees are genuine. Over the years, I have applied a similar proposition to real-life monsters.

Surely, anyone who believes that the Jews are an inferior race, are responsible for the ills of the world, and should be exterminated is, by any definition, crazy. Hitler and Goebbels should share their celestial place of safety with two other tyrants of the 20th century. Only a lunatic, in this case Stalin, would think that the collectivisation of Russian agriculture justified the murder of a million kulaks. And to describe Mao Zedong's behaviour is to realise that, in the language of my schooldays, he was absolutely crackers. He began his career by murdering his enemies and, if Jung Chang is to be believed, ended up watching films of his critics being tortured to death.

It came as a relief as well as a surprise, while reading Erewhon, to discover that I was not alone in thinking that evil can be a sort of illness. Samuel Butler's view is not exactly mine. Some crimes are plainly a sin rather than a sickness. But the legal definition of sanity - the ability to distinguish between right and wrong - is clearly inadequate.

Real madness is the recognition of evil, as defined by rational society, combined with the willingness to ignore the demands of accepted morality. That is not an argument for changing penal policy. Prison may be necessary to keep the miscreants from reoffending and to deter others who are tempted to act in a similar way. To say that some crimes are the product of madness is not to argue that they result from an irresistible impulse.

I certainly had no objection to the sentences awarded after a couple of convictions that made the headlines last week. It just seems worth saying that the criminals in question must have something wrong inside their heads.

Two apparently prosperous young men abducted a youth and, allegedly because he was white, stabbed him repeatedly, doused him with petrol and then set him alight. Do not tell me that such behaviour is the conduct of rational individuals. Another man of about the same age - Hindu by birth and western by upbringing - converted to Islam and decided to devote his life to murdering other members of the community in which he lived. To say that he must be mentally disturbed is a ludicrous understatement. I would have unhesitatingly sent all three to prison for most of their remaining lives.

Treating such crimes leniently is no more sensible than hugging hoodies. But, as a society, we need to understand that such conduct is so deviant it illustrates very little about human nature in general. Whatever the cause of their sin - "original" to some Christians, environmental to determinists, beyond understanding to most of us - their behaviour does not tell us much about the moral state of mankind. Take comfort. Only crazy people behave like that.

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