To describe shopping as the new religion is a cliché. Health spas are the shrines of the modern age and malls are like cathedrals, aren’t they? Well, no, according to Terry Eagleton, who says that we inhabit the first completely atheistic culture in history.

If many of us haven’t realised this, it is partly because plenty of Christians and followers of other religions remain dotted around. But, while physically they - or we - are still very much here, the wider philosophical assumptions that once undergirded the religious worldview have collapsed. In the late-capitalist West, the glue binding people together is not common subscription to eternal truths but a humdrum instinct to keep working – that and democracy, which prioritises change and choice.

Getting rid of God has been a long slog, Eagleton’s concise, absorbing overview of the philosophical and cultural trends of the past three centuries explains. Although the aufklarer - the men of the Enlightenment - started wriggling out of God’s embrace at least 300 years ago, the legacy of centuries of Judaeo-Christian thought initially was too overwhelming for them to see beyond. Successive rebels against the Supreme Being ended up borrowing and replicating most of his attributes, so that while God was dethroned, “understudies”, or “regents”, assumed most of his duties.

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Eagleton says that while most of these philosophical constructs based around the idea of a unifying art or culture foundered because they were too elitist, Romantic Nationalism came close to assuming the form of a real substitute religion. Like early Christianity, nationalism had mass appeal. Like God, the nation was both eternal and was somehow alive, inside people and beyond them. It was the past, present and future. Its heralds were prophets and its difficult birth was made possible by the blood of martyrs.

It elevated its leaders above the normal plain of existence for, as Eagleton remarks wryly, it is very hard to imagine “Pearse or Sibelius chairing a sanitation committee”. Still, it did not endure. Romantic Nationalism has faded, and if a modern nationalist like Alex Salmond were to start speaking about Scotland in the same way that Pearse spoke about Ireland, people would think he’d gone mad. Another god gone, or rendered harmless, at any rate.

At this point, the reader probably thinks: ah, but he has forgotten about the Muslims; their God is not toothless. Well, he hasn’t. Eagleton does not dismiss radical Islam as God’s last throw of the dice in the way that atheists of the Dawkins school tend to. On the contrary, he maintains that atomizing, individualistic Western capitalism has inevitably thrown up a mighty counter-force - a legion of people, and entire societies, which see a godless world of endless choice as a threat. Fundamentalist Islam behaves aggressively, but is, he insists, rooted in deep cultural anxiety. Who will emerge the victor in this struggle, the godless or the believers, he doesn’t say.

In the meantime, the next time you think you are having a “divine” experience in a shop - you aren’t.