Now I know that physiognomy is not an exact science, that one cannot tell a book by its cover, and so on and so forth, but when I saw the mugshots of the four animal rights activists who were sentenced last week to long terms of imprisonment for having terrorised a family of animal breeders, eventually digging up the body of a deceased relative as part of their campaign of intimidation, I understood at once that they did not so much love our furry friends as hate humanity.

One among them, Jon Ablewhite, had been a teacher, and the development of misanthropy in anyone who has had close contact with British youth is only too understandable; while another among them had been a psychiatric nurse, and therefore exposed to some of the less attractive aspects of human behaviour. Nevertheless, there remains something puzzling about their fanaticism. What drove them to such extremes?

When the Soviet Union de facto acknowledged that it had lost the Cold War, I thought that we had seen the end of ideological politics. Marxism being dead, I thought that we had entered an era of rational, if rather dull, compromise: instead of which we have seen the ideological impulse survive and flourish, but in the form of a hundred monomanias. Ideology was privatised along with nationalised companies.

Some people began to understand the world through the distorting lens of one issue: abortion, animal rights, globalisation, anti-racism, even various illnesses, and they formed themselves into pressure groups that in some cases were ready to resort to intimidation, violence and even murder to achieve their ends.

I take it as axiomatic first that human existence is always to some extent unsatisfactory, and second by that most, or at least many, men desire transcendence in the sense that they want their lives to have some larger purpose than the flux of day-to-day existence. Shopping and going to the pub are all very well in their way, but for people of larger spirit they are not enough.

Radical politics answers the need for transcendence and provides a plausible, though erroneous, explanation for the existential shortcomings of human existence. It kills two birds with one stone. It gives a transcendent purpose to life, by allowing participants the illusion that they are helping to bring about a life that is completely without dissatisfaction.

The religiosity of Marxists has long been remarked by the non-believers, the doctrine of Marxism being that history has a plan for the redemption of mankind. When it became impossible for anyone, except perhaps Professor Eric Hobsbawm, to believe any such thing, just as earlier Christianity had lost its credibility for most people, a new outlet for the religious impulse that motivated belief had to be found.

A further two axioms need to be added to explain the rise of monomaniacal fanaticism. The first is that hatred is a much more powerful political emotion than love, and is therefore also a stronger motive for action. It is my guess, for example, that Mr Brown hates the rich much more than he loves the poor, and that anti-racists, for example, hate whites, even when they are white themselves, more than they love members of minorities.

The second additional axiom is that aggressiveness, destruction and violence are their own reward, because they are enjoyable, at least for quite large numbers of people, in themselves. There is also great pleasure to be had from intimidating and striking fear into people. This is no doubt a regrettable feature of human nature, but it is a real one. Anyone who has observed a riot will have been struck not by the misery of the crowd but by its happiness. To feel morally superior while doing evil is one of the most exquisite pleasures known to man.

Not every monomaniac goes as far as the four animal rights activists, but their behaviour was illustrative of the psychology of modern monomania. Their activity gave an illusion of transcendence to their lives, which might otherwise have been mired in the banality of an ordinary existence. Working to save untold numbers of animals from suffering seems more transcendently worthwhile than working towards a pension. And when a cause takes over a mind and dominates it, the existential anxieties of human life — why are we here, what is it all for? — recede very much into the background.

There can be little doubt also that the four monomaniacs took a sadistic pleasure in their persecutions. Their destruction of the peace and tranquillity of other people gave them a great deal of personal satisfaction. This is very primitive: I remember as a boy the joy of pouring boiling water on ants nesting somewhere in the walls of my house, allegedly to preserve the fabric of the house, but really from the joy of cruelty towards living creatures.

Religion is no longer possible for many people, but that does not mean that the religious impulse is dead. Philosophical theories of history, such as Marxism and nationalism, that give life an immanent purpose, have likewise imploded, at least among us in Western Europe, and can no longer satisfy the need for something akin to religion. But there is an infinitude of causes that can give meaning to the lives of those who seek transcendence. Monomania is the perfect answer to all of life’s little problems, providing cruelty for fun and profit.

Theodore Dalrymple is a former inner-city and prison doctor

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