Bill & Ted's Excellent Adventure does not tend to be rated as one of cinema's profounder treatments of the relationship between present and past. The story of two Californian slackers with a time machine who, for complicated reasons, have to assemble assorted celebrities from history in order to pass a high-school project, it is chiefly remembered for bringing Keanu Reeves to the attention of a mass audience. Classicists, however, will always cherish it as the only film ever to combine the music of Van Halen with Greek philosophy. When Bill and Ted embark on their quest, what should be their first destination if not classical Athens, and who should be the very first "historical dude" bundled into their time machine if not a bald-headed man in a sheet whom they persist in calling "Soh-kraytz "?
Even to metalheads, then, the philosophy of ancient Greece serves as something that is both primal and emblematic of civilisation as a whole. Socrates, in particular, the "lover of wisdom" who insisted that the most fundamental presumptions of his countrymen should be subjected to experimental investigation, and who ended up being made to drink hemlock for his pains, has always been admired as the very fountainhead of rationalism. Yet when it comes to identifying what he taught and believed, there is a problem, on which Bill & Ted's Excellent Adventure, rather unexpectedly, puts its finger. Socrates, transplanted to 1980s California, can only communicate with his abductors by gesturing and gurning – since Bill and Ted, it goes without saying, speak not a word of ancient Greek. Even the miracle of time travel, it appears, cannot serve to alter what is, for any historian, a most awkward fact: that it is impossible to be certain of what Socrates actually said.
Like Jesus and, according to Muslim tradition, Muhammad, he never wrote down a word. As a result, it is exceedingly difficult to know anything definite about Socrates as a historical figure. True, we have extensive accounts of what he said and did, and granted, these were composed much closer in time to his execution than were the gospels to the crucifixion, or the first biographies of Muhammad to the death of the prophet. Proximity, however, does not necessarily spell transparency. No matter that the historical Socrates does indeed seem to have patented the dialogue as a form of philosophical inquiry, the surviving accounts of his conversation are very far from being a documentary record. Most of them – perhaps regrettably, from the biographer's point of view – were composed by a man who just happened to be the most influential philosopher of all time, and a supreme literary artist to boot. Write about Socrates with the aim of disentangling the man from the myth, and it is almost impossible to tell where Socrates ends and Plato begins.
This, then, is the treacherous bog into which Bettany Hughes, with her new biography of the snub-nosed philosopher, has fearlessly plunged. She writes as a historian, and her focus, as she is careful to make explicit, is not Socrates's philosophy, but rather how it "evolved in his time and his place". So it is that the life of her hero becomes a peg from which to hang a vivid depiction of Athens in its golden age, from the pinnacle of its greatness to the abyss of its ultimate defeat. To this end, all the talents honed by years of making high-class documentaries about the ancient world are formidably on display. Hughes's prose is the literary equivalent of CGI, re-creating for the reader a sense of the clamour and dazzle of the classical city that has rarely been bettered. Not only that, she is expert in knowing when to alter and vary her focus. Sometimes we are led by her through the streets of modern Athens, sometimes across an archaeological site, and sometimes down into the basement of a provincial museum, where rare treasures lie hidden. She spares no effort in bringing the world of Socrates alive. Describing Athens amid the death-agonies of the Peloponnesian war, Hughes comments that it "must have been reminiscent of Kabul 2002-10: ragged, war-torn, veiled women in the streets with no husbands, brothers or sons". Hers is an ancient Greece that is authentically cutting-edge.
All of which only serves to emphasise the degree to which her book is frustratingly like Hamlet without the Prince. The skill and judiciousness with which Hughes puts together assorted fragments of evidence when writing about Athens is bewilderingly absent from her portrait of the man who is ostensibly her subject. To include great chunks of Plato's dialogues as though they were the ipsissima verba of Socrates himself is cavalier enough. Even more tendentious, however, is the degree to which everything quoted appears designed to make him acceptable to the sensibilities of her readers. That Socrates was a great man is not in doubt; but he was not a great man because he valued women, had his doubts about slavery, or believed in the redemptive power of love. Just as Bill & Ted's Excellent Adventure shows Socrates enjoying the local mall like any west coast teenager, so The Hemlock Cup gives us a portrait of him as a liberal Observer reader. Situated as it is in the midst of such a wonderfully rich and nuanced evocation of the city in which he lived, Hughes's Socrates ends up seeming, if anything, even more anachronistic than does "Soh-kraytz".
Tom Holland's most recent book is Millennium (Little, Brown). 

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...and I am Sid Harth