Leader: Debate is a cardinal virtue, too

Thirty-five craters on the Moon are named after Jesuit scientists and mathematicians. The Catholic Church is often portrayed today as an impediment to science rather than a facilitator of it: the persecution of Galileo looms larger in the collective memory than the exploration of space. But these lunar labels testify that despite the Church's well-publicised run-ins with science, it has also had a long and significant engagement with it. Its followers cannot simply be dismissed as invariably irrational, obscurantist and ignorant.

On the other hand, labels such as these are harder to avoid when Church leaders indulge in intemperate outbursts of the kind made by Cardinal Keith O'Brien at Easter. The Cardinal - a science graduate - described the hybrid animal/human embryos that would be authorised under the Human Fertilisation and Embryology Bill as a "monstrous" attack on the sanctity of life and the experiments of "Frankenstein proportion". The reaction from the scientific establishment ranged from the vehement to the conciliatory, with several experts offering to meet Cardinal O'Brien to explain the science and explore the Church's concern. Nevertheless, the Cardinal achieved his initial objective - the Government conceded that Labour MPs would be given a free vote on the most contentious elements of the Bill. Whatever one thinks of the Cardinal's grasp of science, his political nous cannot be doubted.

Having comprehensively mugged the politicians, the Cardinal is now preparing to deal with the scientists. Although a date for the discussion has yet to be confirmed, the Cardinal hasn't been idle. As well as expanding his ideas in a blog, he has posted a five-minute harangue on YouTube. He claims that the lack of scientific rigour in the embryology experiments worries him as much as their immorality. Cardinal O'Brien is being disingenuous. Even were the experts to allay his scientific doubts, his conscience would not be calmed. The root of his implacable opposition is his and his Church's belief in the sanctity of human life, which, they argue, would be apparent, and grotesquely violated, even in the tiny, fleeting existence of a hybrid embryo.

On one level, the Cardinal's actions are perfectly justifiable. If one believes that life begins at conception, however unorthodox, then what merit temperance? Is there not a duty to be loud in its defence? It is, as events have shown, effective. And the Cardinal has form. Last year he compared the current abortion rate to "two Dunblane massacres a day" and thundered: "We are killing in our country the equivalent of a classroom of kids every day."

But if one does not accept his religion's ethical proposition about human life, what kind of discussions are on offer? Interestingly, he has told us: "In agreeing to such a meeting, my only condition would be that the scientists were also willing to accept instruction from our churches and peoples of faith on basic morality, on what human life really is, on the purpose of our life on Earth and so on." If his interlocutors do not have any qualms about the first part of that sentence, they surely should have about the "and so on". It has an infinite ring to it.

Rhetorical thuggery can advance an argument an awfully long way. The danger is that the more extreme the position, the easier it is to dismiss. Complex matters are obscured in a tidal wave of invective. And that is a great pity because the issues created by scientific advances require ethical debate. That is easy to avoid when one's opponent can be caricatured as a theological Rambo. Cardinal O'Brien is an excellent politician but a lousy philosopher. He cleaves to certainty and does not acknowledge the value of doubt. Are there any features on the Moon bearing his name? Possibly, in the Mare Fecunditatis or the Mare Spumans.

gerard.kelly@tsleducation.com