It is a question much in the air as a new biography of Marx, by French polymath Jacques Attali, argues that Marx was a free-marketeer and a prophet of globalisation. This comes on the heels of Marx's unexpectedly comprehensive win in Radio 4's search for the Britain's favourite philosopher last year. The profile of Karl himself couldn't be higher. But that of the explicitly Marxist intellectual is shrivelling. As Marx is rebranded as economic analyst and philosopher whatever happened to his call for workers of the world to unite – and change it? In this issue we feature a number of leading figures who, after rising to prominence as thinkers, dissenters and debunkers, with a fully-acknowledged allegiance to Marxist ideas, now appear to be struggling to find a voice and a role in a transformed world.

For more than four decades, Professor Stuart Hall has been revered as one our most ingenious and creative academics. Whether it was devising the tools by which to decode the media, long before media studies existed, presiding over the vastly influential Birmingham School of Cultural Studies, or explaining the significance of psychoanalysis and post-structuralism, he has long been regarded as one of the finest minds and communicators of his generation. And through it all he was a Marxist. Now he feels disillusioned by the way the world has turned. But he is still a Marxist. On page 14 he tells Laurie Taylor why.

Sociologist and cultural critic Perry Anderson, founder of New Left Review and in-house inspiration for a whole cadre of the left, also seems to be grappling with a void. In his review of Anderson's new book of essays Stephen Howe finds another mighty Marxist intellectual nonplussed by events, but still holding his own.

It's not just progressive thinking that is under siege. So is rationalism, according to David Katz who, in our cover story (page 10), chillingly reports that It's not just a few cults and extremists who have developed fanciful notions about how and when the world will end. It's powerful leaders, east and west – who also have the means to make it happen.

The rise of fundamentalism – what Stuart Hall calls the 'revenge of culture on modernity' – is just one of the pressing contemporary issues which has have blindsided theoretical Marxism and the left in general. The times demand new methods and new approachs. Where are they? But it's not all doom and gloom. In a rousing call to arms, Stephen Eric Bronner (page 24) urges the progressive left to reclaim Enlightenment values – a radical ethos – which is in danger of being hijacked by neo-Conservatives in America. There is a note of stirring optimism in Bronner's argument which marks it out rather sharply from the melancholic tone we are hearing from European intellectuals.

And there's more optimism this issue as we celebrate high humanist culture. We mark the anniversary of Samuel Beckett's birth with a reconsideration of his morbid genius. Beckett may not normally be hailed as a tonic to the human spirit, but Nina Power's refreshing reassessment finds hope among the garbage cans and in the tenacity of his cast of sufferers and survivor. In the centre pages Hugh Pearman takes us on an authoritative tour of architectural Modernism. Though its socialist utopianism may now seem outmoded, the desire to create a rational world, uncluttered by the baggage of the past, is enough to uplift even the most weary atheist soul.

A date for your diaries. In collaboration with the Institute for Public Policy Research we are holding a conference, on March 21, on religion and politics called 'State of Faith'. In addition to a keynote speech by Home Secretary Charles Clarke it will feature Stephen Eric Bronner, Jonathan Rée, David Aaronovitch and Bhikuh Parekh. It's free but you need to reserve a place – you'd be very welcome to join us. See page 43 for details.

As we go to press we hear the sad news of the death of Linda Smith, comedian, president of the British Humanist Association and honorary associate of the Rationalist Association. Linda combined a delicious and sometimes wicked sense of humour with a real appetite for life. Not only was she one of the country's most successful comedians, she also found time to be a tireless advocate for humanism.