An intellectual biography of the the 14th century Arab historian variously claimed as a precursor of Montesquieu, Comte, Spengler and/or Gibbon, not to mention a founding influence on sociology and economics, and an inspiration for Asimov’s Foundation and Herbert’s Dune. But one of Irwin's recurring themes here is that those who come to Ibn Khaldun tend to envision him in their own image, however much fancy footwork that may require. Irwin seems to have resisted that temptation as best he's able: the abiding impression he gives is of a man who was fascinating but also infuriating, and Irwin is careful to emphasise that for all we might have in common with people in the past, there is also much that divides us. On the one hand, a 15th century polemic by one of Ibn Khaldun's followers makes the observation, still sometimes considered satirically viable today, that breathing is pretty much the only thing not taxed. On the other, this is someone who for all his insights, was somehow convinced that it was impossible to die of starvation. Similarly, for all that he anticipates Adam Smith in his observations on the division of labour, Ibn Khaldun was convinced (despite evidence even in his own time and place) that gold and silver were divinely ordained as measures of value, and as such not subject to fluctuation. The speech in which Ronald Reagan (mis)quoted his ideas necessitates the sub-chapter head 'IBN KHALDUN DID NOT INVENT THE LAFFER CURVE', but in some ways you could say their interest in divination and their faith-based economic policies made them bedfellows of a sort. Still, at least Ibn Khaldun understood that there was little real difference between trading and gambling - something which continues to escape a surprising number of people today - even if he did also believe that one of the key arguments against hoarding was that a hoarder “is persecuted by the combined psychic powers of the people whose money he takes away” - a pleasing notion of psionic proto-Marxism which, alas, doesn't seem to be having much impact on the modern 1%.

Still, the real focus is on Ibn Khaldun's theories of history, his search for its interior meaning or 'batin' as against the mere externals or 'zahir'. He was much preoccupied by the notion that settled civilisations fall into decadence, at which point they are conquered by nomadic people possessed of more primitive vigour...who promptly settle down, and the cycle repeats. But unlike the Spenglers or Gibbons of this world, he was broadly in favour of this. It's that same hypocritical hard-on of the soft academic for the rough boys which goes back at least to Plato's grubby fascination with Sparta, and still replays as farce in rock critics' inexplicable pretence that there's anything interesting about the Gallaghers, or the leftwing liberal's defence of the dictatorial strongman just so long as he's foreign. Irwin notes that, having begun with these theories, Ibn Khaldun's work doesn't actually do a great deal to live up to them, and that beyond a few set-pieces his actual histories are fairly standard affairs, not even as colourful as those of Western contemporaries who were already writing in a more literary and rhetorically lively style. But as Irwin also notes, it's debatable whether any one man's attempt at a comprehensive history could live up to Ibn Khaldun's prospectus, even if that man were himself. Still, you can see why – whatever its flaws – it might appeal to the likes of Toynbee in particular, who loved the combination of grand design and mystical faith. Something Hegelian there too, of course, though Hegel and Marx were both considerably more convinced of the possibility of progress than the doom-laden Ibn Khaldun.

Irwin has elsewhere written persuasively of the problems with Said’s broad-brush attacks on orientalism; still, it is noticeable that until the tenth chapter, on the cultural afterlife of Ibn Khaldun and the Muqadimmah, when he quotes secondary sources the writers tend to have European names. It turns out that this is at least in part because for a long time Ibn Khaldun was a classic prophet without honour in his own land, being adopted first by Ottomans and then Europeans before finally making his way back to the Arabic world. And Irwin certainly neither shies away from nor approves of the ways in which his subject was adopted and misrepresented by colonialist projects, who tended to see Ibn Khaldun as sui generis, both supporting and himself a unique exception to an imperially convenient narrative of the perpetual strife and indolence of the Middle East. Although for all their sleights of hand, you can see why colonialists might have been drawn to a thinker who suspected that the great age of the Arabs was over, and the torch of civilisation passing to Europe. Irwin, on the other hand, is always careful to dig back down into Ibn Khaldun’s own milieu and the currents of thought among which he moved – Sufism, Maliki jurisprudence, the Ash'arite occasionalism which held that "What we call cause and effect are nothing more than God's habit.” Yes, he’s obviously fascinated with the earlier era of orientalists – the colourful likes of Joseph von Hammer-Purgstall, one of the key figures in bringing Ibn Khaldun to European attention, or the equally brilliantly named Reinhart Dozy, whose bellicosity gives the lie to nominative determinism. But he generally manages a wonderful balancing act of being at once magisterial and humble. “Who was Ibn Khaldun writing for? Well, certainly not for me. Nor, come to that, for the massed academics of the twenty-first century world…I am conscious that I have sometimes failed to understand what Ibn Khaldun is saying”. As when Bertrand Russell occasionally admits to not following some particularly abstruse manoeuvre by the scholastics, there are few things which make me trust an expert so much as a frank admission that even they can’t follow everything. On top of which, he has a lovely turn of phrase, as when Ibn Khaldun meets the conqueror the West tends to know as Tamerlane: “Timur, for his part, was fond of historians (though they seem to have been less fond of him).”