In Woody Allen’s new film Irrational Man, Joaquin Phoenix plays a morbid, cynical, dissolute, paunchy, middle-aged college professor who gets a new lease on life after he jumps into bed with a student half his age. It helps that the student is the buoyant, radiant Emma Stone; it also helps that the reliably off-kilter Parker Posey, playing a hard-drinking, unhappily married chemistry professor, is also available for emergency house calls. The moral of this story? When gazing directly into the abyss, there’s no better pick-me-up for a maudlin, middle-aged dipsomaniac than a tag-team pair of star-struck female admirers.

As in so many of Allen’s movies, Irrational Man is the kind of film where academics pompously toss around names like Kierkegaard and Heidegger and De Beauvoir the way we all did when we were 19, until our dads said they would smack us if we mentioned Camus one more time at the dinner table. What rescues Irrational Man from being like every other film about conceited, self-absorbed, self-pitying ivory-tower denizens is Phoenix’s gradual migration toward a highly personal brand of philosophically justifiable homicide as a means of bettering society at the grassroots level. In other words, unlike most films about pretentious, neurotic academics, something exciting actually happens in Irrational Man. In fact, a couple of things. Including Russian roulette.

Joaquin Phoenix cosies up to Parker Posey in Irrational Man. Photograph: Sabrina Lantos/Allstar/Sony Pictures Classics

Academics have been popping up on the silver screen an awful lot lately and nobody is entirely sure why. Really, really smart guys – and one gal – from Cambridge and Oxford join forces to put the kibosh on the Third Reich in The Imitation Game – the RAF, the Red Army and the US navy simply weren’t equal to the task – and the smartest person in the entire world explains how the universe works in The Theory of Everything, an achievement all the more remarkable because he does this after falling victim to motor neurone disease. Meanwhile, a has-been English screenwriter takes a job teaching at a so-so state school in upstate New York in The Rewrite. Before that, in Liberal Arts, a burned-out admissions director goes back to his beloved old college in Ohio to visit his beloved old poetry professor and possibly sleep with the professor’s beloved 19-year-old daughter. In all of these films, guys with a few screws loose are rescued from the emotional doldrums by stolid, absolvent, uncompromisingly supportive women who are happy to sleep with them, even when the men are not especially nice. Some of these women, it should be noted, are not yet old enough to buy liquor. So the professors have to bring their own.

Why are these women attracted to these bloviating nebbishes? Why do they put up with all this gasbagging about Nietzsche and quarks and black holes and Nazi algorithms? Because smart is sexy. Very, very sexy.

Keira Knightley, left, and Benedict Cumberbatch, centre, crack codes in The Imitation Game. Photograph: Allstar/Black Bear Pictures

Movies dealing with similar, and in some cases identical, themes tend to arrive in bunches. For years on end there will be nothing but films about dirty cops and misunderstood vampires and intransigent zombies. Then all of a sudden, from out of nowhere, there will be a ton of movies about men who fall in love with artificially intelligent women (Her, Ex-Machina, Tomorrowland), or movies about perky teens trapped in a dark, dystopian future where they are forced to wear glorified pajamas in public, or movies about eastern European gangsters with appalling social skills who do not like Liam Neeson.

For no reason whatsoever, there will be a whole slew of films about sexy architects or prodigiously gifted chauffeurs or affable American presidents. You turn away for a second and inexplicably, without a word of warning, every other movie features a cute little doggie named Buddy or flying sharks or Wyatt Earp or Melissa McCarthy.

Alfred Russel Wallace ... not famous due to some kind of Darwinian process. Photograph: Hulton-Deutsch Collection/Corbis

This is because of the theory of creative simultaneity, which stipulates that great ideas always occur to at least two people at exactly the same moment, especially in Los Angeles. Alfred Russel Wallace and Charles Darwin separately and simultaneously developed the theory of evolution. Cortez and Pizarro separately and simultaneously came up with the idea of invading powerful empires in the new world and stealing everything that wasn’t nailed down. Hitler, Mussolini and Franco had exactly the same bad idea at exactly the same time. The Backstreet Boys and ’NSync are almost perfect contemporaries. So are the Ramones and the Sex Pistols. Bach, Handel and Scarlatti were all born in 1685 and all became famous writing complex, almost mathematical, music with lots of ostentatious ornamentation. What were the odds of that?

In short, the arrival of a deluge of movies about academics, and especially British academics, should come as no surprise. The movie industry is dominated by people who went to the right schools, so they make movies about other people who went to the right schools, even when these other people went to a different right school than they did. This is why there are loads of movies about people who went to Cambridge and Oxford and Harvard and Yale, but very few about graduates of the University of Birmingham or Central Connecticut State. The moviegoing public, it is assumed by those in the know, are only interested in seeing films about the best and the brightest, not the beautiful and the damned or the naked and the dead. It’s nothing personal; it’s just the way life operates.

Academics have long fascinated moviemakers, though only a particular kind of moviemaker: the ones who go through their entire career without once filming a human being getting impaled on a gigantic, sharpened bamboo shoot. Academics play pivotal roles in everything from The Blue Angel (schoolteacher destroyed by ambitious, scantily clad chantoozie) to Goodbye, Mr Chips (lovable schoolteacher behaves lovably to lovable public school boys) to A Beautiful Mind (mentally unstable academic wins Nobel prize and the right to date Jennifer Connelly). Academics command centre stage in Dead Poets Society (public school boys find themselves smitten by charismatic teacher) and Good Will Hunting (caring academic encourages protege to give up his job as a janitor) and Wonder Boys (creative-writing professor has midlife crisis) and The Emperor’s Club (beloved old prep-school teacher discovers one of his old students is a scoundrel) and even Larry Crowne (gin-monkey college professor finds true happiness with ex-box-store manager who belongs to a local moped gang).

Robin Williams inspires some schoolboys in Dead Poets Society. Photograph: Sportsphoto Ltd/Allstar

Why are movies about academics so popular? Theories on this subject abound. For starters, contemporary literary fiction is filled with academics, because most fiction writers are academics. Observing Ernest Hemingway’s dictum to write about what they know, they write about themselves. They do not write about pediatricians or chartered accountants or goalkeepers for Derby County or tough customers who work on oil rigs in the North Sea, because those professions lack glitz and panache. Chartered accountants never talk about Heidegger and Kierkegaard. Oil-rig employees never mention Simone de Beauvoir. The crew would toss them overboard if they did.

To look at films such as Irrational Man and The Imitation Game and The Rewrite, you would think that academics, in their own low-key, velocipedic fashion, are incredibly interesting and even sexy. In reality, this is only true if the movie stars Julia Roberts (The Mona Lisa Smile, Larry Crowne); most academics are dorks. But in the end, the real reason for the continued veneration of academics by film-makers may be purely economic: films about academics rarely have scenes where Death Stars explode or planets implode or helicopters crash into the sides of mountains, so they’re cheap and easy to make. Films about academics can always be brought in under budget. You don’t have to set aside any money for special effects. You don’t have to set aside any money for massive traffic accidents where 14 LAPD cop cars get destroyed or Mars explodes. And you certainly don’t have to pay for an army of computer-generated orks.

None of whom went to Harvard.

• Irrational Man is out in the US on 17 July and in the UK on 11 September.