Only a few years ago it might have been assumed that secularism and rationalism were so accepted and universal that there was no need to defend them. But it's become increasingly clear that this is not the case. Humanism and rationalism are under attack, not just from the churches and mosques but from a dizzying variety of religious, superstitious and irrational systems of thought. And it's the job of this magazine to defend them. That was the challenge and I welcomed it. But about two weeks after I started at the offices on Gower Street, this somewhat abstract goal suddenly became more concrete and immediate. Arriving at my office by bike I was struck by the clusters of people on the streets staring perplexedly at their mobile phones. As I reached my desk the flimsy official explanation – a major power failure on the tube – unravelled as news of the bombs on the tube filtered in. The Tavistock Square bus must have exploded just as I entered my office – only a few streets away. That afternoon, In the eerie aftermath, we straggled through the empty streets to a shell-shocked pub where, as we huddled over our beers, we wondered just how far the devastation had been inspired by religion at its most fanatical.

That was when the abstract and the concrete merged – when for me the requirement to speak out against religious intolerance and dogmatism, hatred and inhumanity, extremism and false promises of paradise became not just a professional duty but a personal necessity.

This issue showcases an eclectic range of responses to the irrational. First of all – the political. Isabella Thomas offers a highly informed analysis of Fidel Castro's hold over Cuba and his incredible powers of survival. Sunny Hundal and Jeremy Strangroom intervene in debates about freedom of speech and the nature of truth, while Merlin Holland, grandson of Oscar Wilde, reports from Moscow on the alarming suppression of gay rights.

Then there's the philosophical. AC Grayling steers us through Kant's wonderfully subtle demolition of theism, while Michael Marsden uncovers the religious imperative behind the startlingly popular Alpha course. We enter into complex contemporary debates with Stan Cohen's discussion of the politics of apology, and Jenni Murray's passionate polemic on the rights of the dying.

And finally, there's art: from the art of comics to the artistry of John Coltrane, we have plenty of brilliant insights to remind us of the pricelessness of culture and art in the making of a free and open society. The idea of the artistic genius as a rebel and outsider may, as Lynda Nead suggests, be a creation of 19th century romanticism. But the role of the artist remains crucial – any society is made worthwhile, brought to life and enriched by the art it produces.