A good, beneficial multicultural society is one in which everyone has the freedom to pursue their own different ethics and lifestyles, while in the public sphere all citizens are treated as equals and are bound together by a shared commitment to universal human rights, regardless of the differences in their personal morality and private lives. I do not, for example, insist that people of faith approve of homosexuality, but I do expect them to not discriminate on the grounds of sexual orientation.
Where some strands of multiculturalism have gone off the rails is in their institutionalisation of difference through initiatives like the state funding of faith schools, which factionalises pupils along religious lines.
Another big error by some multiculturalists has been to bow to demands for cultural sensitivity by tacitly accepting that some peoples and communities can be exempt from the norms of universal human rights.
Moral and cultural relativism have gained ground. We are told every community is different. All these differences are equally valid and must be respected. To question them, we are admonished, is to impose our way of life on others – a form of cultural imperialism.
It is true there is no one-size-fits-all blueprint for all societies and communities. But are there no universal humanitarian values that should be defended in all cultures at all times? Is everything relative? Should we accept practices in other communities that we would never accept in our own? Allowing people in developing countries to suffer indignities that we would never tolerate in our society is a shameless double standard. It smacks of racism.
All peoples possess a culture, but this does not mean all cultures are equally valid and commendable. Some values and ideas are better than others. The Enlightenment was better than the Dark Ages. Freedom is better than slavery. Democracy is better than fascism. Scientific knowledge is better than superstition.
While all human beings deserve human rights, not everyone's beliefs and traditions deserve respect. Political and religious ideas based on racism, patriarchy and homophobia are unworthy of respect. They need to be challenged, not tolerated.
This is an extract from a lecture at the Gallery of Modern Art, Glasgow, last week