Informed by Durkheim's early attempts to understand the epidemiology of suicide, and by that of many subsequent investigators, the bare statistics can be contextualised in an attempt to make sense of the experience of individual countries. Ireland is an interesting case in point. Until the early 1970s, the number of suicides in the country was very small. The graph bumps along the bottom, barely seeming to register at all. Then, in the '70s, something significant happens. The rate starts to climb and does so, steadily, over the next 30 years, reaching a peak in 2000 at a level one - third higher than the UK's and somewhat above the Western European average (it is now the fifth highest in the EU). Those same three decades were, of course, a period of rapid change in Ireland. From being a confessional nation, where religious observance was nearly universal, it turned into a more secular and materialistic society. Plenty of Irish people are still practising Catholics, but secularism has got a grip especially among younger people. Ireland has also become very much more prosperous. The generous Celtic Tiger has distributed largesse - albeit unevenly - around the population.

Dr John Connolly, a consultant psychiatrist who heads the Irish Association of Suicidology, candidly admits he has no satisfactory explanation for the increase but if pressed he cites the decline in religious observance, a creeping materialism and the explosive growth in alcohol consumption. He claims there is a direct correlation between alcohol consumption and the suicide rate. The link between prosperity and suicide has long been noted - it is the better-off who are more at risk. At the Oxford Centre for Suicide Research, Professor Mark Williams makes a more nuanced connection; he believes it is disparities in wealth that matter. Inequality, in his view, is a driver of suicide which is why the rate of suicide has increased so dramatically in Westernising economies like China.

Russia's experience has something in common with Ireland's. Until 1990 its suicide rate - though high by Western European standards - was on a gently declining trend. Then came massive upheaval as communism collapsed. Over the next five years the Russian rate shot up, then peaked and stabilised at a rate of nearly 40 suicides per 100,000 - that's about six times higher than the UK. As in Ireland, the consumption of alcohol has increased markedly over the same period. Also as in Ireland, a hegemonic belief system - communism - was challenged and dethroned. Changing times, it seems, encourage suicide.

In Britain - it can be predicted with some certainty - the suicide rate will rise in the near future because of the recession. Looking at the statistics, the same phenomenon can be observed in previous recessions. But it is striking how stable the British suicide rate has been over the decades. It peaked in the mid 1950s at 10.7 per 100,000 then fell away, reached another peak in 1985 - nine suicides per 100,000 - and has fallen back again reaching a low of 6.7 per 100,000 in 2005. It would be higher were it not for the endeavours of mental health professionals, whose efforts to prevent suicide can claim at least some success. Attempting to save the lives of those in despair is a noble endeavour which perhaps reflects society's instinctive abhorrence of suicide. The suicide taboo has been recorded across nearly every human society (perhaps because suicide so obviously imperils the future of any society). The literature on the subject is full of picaresque detail. In 18th century Massachusetts, a stake was driven through the heart of the suicide. In medieval France, the corpse of a suicide was dragged through the streets, head down, then hanged on a gallows. In ancient Greece, the hand by which the suicide died was severed from the corpse and disposed of separately. Dante's Inferno demonstrates the profound Catholic strictures against suicide; he has them condemned to the seventh circle of Hell where their souls are transformed into bleeding trees constantly tormented by harpies. All these examples - and there are many more - speak of the deep upset people feel when the survival instinct, that mainspring of our animal existence, is abrogated.