There are two rarely noticed facts about drugs. First, almost all human beings use them - alcohol and nicotine included. Secondly, drugs became illegal less than a century ago, first for soldiers in the First World War, who used them to combat the horrors of the trenches, and then as part of the “prohibition” lunacy, in which both drugs and alcohol were banned in the United States. As Prohibition proved, outlawing things is a godsend to criminals, who are energetic entrepreneurs and who will provide what people want at great profit to themselves and great cost to society.

Cannabis became more dangerous this week, not because of anything intrinsic to its chemistry but because the Home Secretary said so. It has been moved from Class C to B. At the same time moves are afoot to downgrade Ecstasy from A to B.

Since the dawn of history people have wanted to ingest substances that alter their states of consciousness, whether for relief, recreation, spiritual experience or bliss. Coffee and chocolate are also mood and mind changers. If moralisers were logicians these would be outlawed too. At the very least alcohol, as dangerous as some of the other commonly used drugs, would be banned. Or, more sensibly, every other drug would be controlled, as alcohol is, thus at a stroke liberating the police, the public purse and the populace, who would not become any more drug-crazed than they were before 1914.

A.C. Grayling is Professor of Philosophy at Birkbeck University of London

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