Off to prison to visit a writer friend, first jailed led some years ago for trying to find a hit man to kill his mother’s toy boy. My friend had no objection to his mother having boyfriends per se, but what irked him was that she’d left the toy boy her house. After good behaviour, my friend was released on the condition that he would not leave the UK. But he did, phoning every so often from unexpected places such as Lake Geneva and Chartres. A court meanwhile had awarded him the house, so the hit man had been unnecessary. Last year, re-entering the UK by plane, my friend was met by police and taken away in handcuffs. Thanks to the Howard League for Penal Reform and English PEN, the ban on prisoners receiving books is over, so at least he can read.

When I arrive at the prison, my friend is waiting for me in a red prisoner’s over-vest, and he seems perky. I buy him a Galaxy bar from the café at the edge of the room and encourage him, now that he has time, to write. He will, he says, but only when he finds out the true identity of his mother’s toy boy and how the interloper wheedled his way into his mother’s life. I make a note to buy him some books. Crime and Punishment, perhaps?

My son Nicholas, 31, who has Asperger’s syndrome, often defends the vilified. At a special school, when aged seven and asked by the teacher: ‘Was Henry VIII a good man?’ he replied: ‘Yes.’ She was annoyed. He told me later: ‘I had the right to say that.’ Other baddies he’s championed are the vengeful woman in the film Fatal Attraction, and Jimmy Savile, who he feels sure must have done at least one good thing. Nicholas is a painter and he has taken great pains with a portrait of Karen Matthews, who in 2008 helped to stage the kidnapping of her daughter Shannon. The head of one of Nicholas’s old schools was tried recently for 24 charges of indecency. Nicholas, who’d lasted at the school for 12 days, again took a lenient line, saying he’d liked the man.

Is it Nicholas’s unusual brain chemistry that make him react differently? I’ve been told that those with autism, bipolar disorder and indeed with almost every psychiatric disorder have an abnormal, or non-neurotypical, amygdala. The amygdala is an almond-shaped lump of neurons deep in the brain. I once attended a lecture given by a Dr James Blair, of the American National Institute of Mental Health, who told us how psychopaths’ behaviour is caused by their deficient amygdalas. The characteristics of a psychopath are glibness, superficial charm, lack of remorse, lack of empathy, promiscuity, failure to accept responsibility, lack of friends and lack of long-term goals. I was worried at the time that several of these applied to Nicholas. But a lack of empathy? It seems to me that my son’s defence of the worst of humanity indicates that he is capable of more, not less, empathy than most normal people.

How different America is from Britain. I have visited recently and come back surprised by our differences in what we say and mean.

American         British
‘I’m good’       ‘I’m OK, thanks’
‘I’m mad’         ‘I’m angry’
‘I’m pissed’    ‘I’m annoyed’
‘Popover’        ‘Yorkshire pudding’

Another difference is the close alliance between money and spiritual matters in America. My father, who was hysterically anti-American, was shocked by his first mass in an American Catholic church in the late 1940s, when the priest said he only wanted to see ‘greenbacks’ (dollars) in the collection box. The most extreme example of this unholy alliance occurs in what my Florida friend calls ‘the death industry’. My friend and her siblings had discovered that the expensive funeral company which had buried both their parents had made a mistake and had put their father in a grave on top of a neighbour, Mrs Curtis. Their mother had ended up on top of Mr Curtis. The funeral company, loath to fork out for a relocation, had tried to cover up their mistake and my friend’s sister sued. It took her several years to win her case and during that time she had to visit the dug-up graves and view decomposing corpses. My Florida friend, who normally has a wacky sense of humour, told me this story with utmost seriousness. Personally, I would have left my parents with the Curtises, but I did not tell her that.