Earlier this year, I spent a pleasant and useful evening with the academic who has just (briefly) become The Most Hated Man in Britain. Asked to chair a panel on science writing and its limits, I had invited along the author of Beyond Evolution (Oxford, pounds 19.95) - a lucid philosopher's critique of the neo-Darwinist biology that hogs so much media limelight these days. I would strongly recommend the book to anyone who feels at all suspicious about the reductive blueprints of mind or society that win such an easy ride on Start the Week. Anthony O'Hear frames some cogent objections to the all-in-our-genes brigade, but he also manages to give a fair account of the case he opposes.

So does his essay expressing a few reasoned doubts about the late Princess of Wales's philanthropic role. Not, of course, that you would know that from the revolting Stalinist witchhunt - pursued all the way from 10 Downing Street to the mindless dregs of the red-top press - that gave the hapless O'Hear many more than 15 minutes of infamy.

As it happens, I disagree with O'Hear about the meaning of Diana's death. He underestimates her, and her supporters. So what? He made an intellectual error. An error is not a crime. Yet this mild essay unleashed a torrent of abuse that for a while pushed him ahead of child murderers in the tabloid roll of dishonour. Worst of all - by a very long chalk - a prime minister with a 178-seat majority took the time to intervene and deliver another kick to the persecuted prof. Even in her battiest days of pomp and paranoia, Baroness Thatcher never did that when the likes of Stuart Hall or Eric Hobsbawm had a bash at her.

One thing has not changed a bit since the Thatcherite high tide. In a climate of authoritarian populism, any truly unorthodox view must be branded `snobbish' or `elitist'. Those curses work in Britain today much as `Communist' did in McCarthy's America or `Rightist' in Mao's China. They place the heretic beyond the pale. We're all meant to be zany individualists now - but woe betide the oddball who really rocks our boat. As John Ralston Saul puts it in his new book The Unconscious Civilization (Penguin, pounds 7.99), `the practical effects' of this mixed-up mood are `passivity and conformism in the areas that matter and non-conformism in the areas that don't'.

A Canadian, Saul is an oil executive turned social philosopher who delivered the essays in this book as the Massey Lectures (Canada's version of the Reith Lectures) in 1995. He argues, sometimes with more passion than precision, that our rhetoric of the free market masks the dominance of corporatism. By this he means the anti-democratic manipulation of interest groups by central power in the cause of preserving social order and inequality.

Saul can be a wild and woolly thinker. He blurs the boundaries between open and closed societies too glibly. Yet his scatter-gun polemic does help to explain how a culture that trumpets choice and risk can often feel so stiflingly single-minded at crucial moments. When simple dissent from a majority media view can call down the wrath of the government machine, we have other things to mourn beyond the death of a kindly princess.