The best witty banter in all of Golden Age cinema probably belongs to William Powell and Myrna Loy in the Thin Man series as Nick and Nora Charles, but their onscreen partnership also represented a pretty unusual relationship for the time: an equal one. Powell was the detective and Loy his wealthy wife, but both came into it with equal financial and societal power, they displayed strong mutual respect and affection (while still teasing each other constantly). They both had brains, and they were, at all times, a team. It's always been thought that writer Dashiel Hammett based it on his long-term relationship with writer Lillian Hellman. Even though Loy was clad in the restrictive fashions of the 1930s and undercurrents of sexism ran strong throughout every plot in the series, the central relationship, in its own weird way, remained on a perfectly even keel. It's a good lesson: that if equal relationships can be possible even when you're being chased down by the mob or seeking out mysterious murderers in the 1930s, they're possible now.

If there's one thing you get in great abundance in screwball comedies from Howard Hawks and his ilk, it's arguments — between prospective lovers, actual lovers, husbands and wives, and misunderstanding suitors alike. The most pertinent example is Cary Grant's rapid fire, frustrating exchanges with oddball heiress Katharine Hepburn in Bringing Up Baby, in which neither party can make themselves understood without a dictionary or a sedative; but My Man Godfrey, which features William Powell (again) continually attempting to talk sense to the charmingly daffy Carole Lombard, is another excellent entry into the genre. The arguments may be rooted in fundamental differences, they may end in utter frustration and drive audiences to distraction, but they can also foster love, and are used as a shorthand for getting to know one another better. Nobody who watches movies like these comes away afraid of a good fight with a lover.

The comedies of old Hollywood are crammed full of people blissfully unafraid of looking completely daft for the sake of love - or for amusing their partners. Silliness is a thing to be embraced, dignity isn't relevant when you're with your partner, and people who don't appreciate either of these facts are to be viewed with enormous suspicion. The annals of the films of the period are filled with people committed to being complete idiots in the name of romance: William Powell in Love Crazy actually feigns being a lunatic in order to delay his wife's divorce proceedings (at one point addressing a concerned passerby as General Electric Whiskers), while Irene Dunne, in The Awful Truth, plays the point par excellence when she wins her ex-husband, played by Cary Grant, back by turning up to his new fiancee's party and performing a completely daft burlesque number (watch it, you'll understand).

But being a fool for love isn't the only act: the best couples are the ones who are foolish in love. In Topper, the staid Topper (Roland Young) revitalizes his relationship with his wife Clara through the interference of two fun-loving ghosts. And Roman Holiday features Audrey Hepburn and Cary Grant having madcap fun all over Rome. If you can't go loony with a lover, what's the point?

Sometimes the lessons to be learned from old movies, at least in my experience, are decidedly negative. This is unsurprising considering how old many of them are (coming up on their 100th birthday, in some cases), with the attendant gender mores and archaic patterns of behavior. But what's given as a "happy" ending can be educational even when it appears to be less than charming. In His Girl Friday, crack reporter Rosalind Russell is lured away from her romantic, dependable fiancé (Ralph Bellamy, who does nothing whatsoever to cause offense besides being boring) to reunite with her ex-husband, newshound Cary Grant, who puts his job first and her second. It's a feminist film in that Russell's character realizes she can't give up her job as a reporter, because she loves it too much — but Grant's selfish bossiness as preferable to Bellamy's adoring gentleness never struck me as a good model for anybody.

Being the straight man in a joke is rarely a good time — and Margaret Dumont, the actress who starred as Groucho Marx's love interest and frequent joke-target throughout many of the Marx Brothers films, represented an acute lesson in taking other people's nonsense. Dumont was a woman of great elegance and character, at least a foot taller than Marx, and their dynamic was usually the same: she would play a rich widow or society woman, Marx would make love to her while also making frequently insulting remarks about her face, figure, intelligence and everything else, attempt to pick up every other woman in sight, and in the end would condescend to finally marry her. Dumont was doubtless never meant to be a cautionary tale (she always melted into Groucho's arms with great alacrity at the end of the films), but the idea of constantly being teased and told mean-spirited jokes, and expected to stand it because of love, loomed alarmingly as a Bad Idea.

Some of us continue to be taught that the best relationships are smooth sailing all the way. That sort of thinking is decidedly absent from many Old Hollywood films; people get together or come back together through coincidence, mishap, complete disaster, or split-second planning. (Con artist Barbara Stanwyck orchestrating a meeting with Henry Fonda's rich brewery heir by sticking out a leg and tripping him over in The Lady Eve comes to mind.) In these film relationships, accidents are a constant, and the more people attempt to plot a course securely, the more it wriggles out of their hands and goes completely haywire, but the end result ends up better because of it.

The film The Women is famous for several things, most notably for not featuring a single man in the cast — and therefore for placing the blame for a lot of the film's romantic drama on the women themselves. The "men can't help themselves" idea around adultery that pops up in this and many other films is daft, but when Norma Shearer decides to kick out her cheating husband and let him marry his mistress, the deliciously evil Joan Crawford, it's heavily implied that his betrayal was one thing, and her refusal to try and work things out was another. (Of course, they end up together again.) Stripping that lesson of its heavy sexism still leaves a germ of truth.

And the value of attempting to work with the flaws of lovers runs strongly through The Philadelphia Story (in which Katharine Hepburn's intolerant heiress learns to be more accepting of faults when she herself makes a large mistake) and even Some Like It Hot. The Billy Wilder film's classic final line, in which wealthy Joe E. Brown meets a drag-clad Jack Lemmon's revelation that he's actually a man with a serene "Well, nobody's perfect," is one of the funniest arguments for warts-and-all love in all of movie history.

If there's one consistent relationship lesson you can take away from the comedies of the Golden Age of Hollywood, it's that communication is key. Nick & Nora Charles are the only couple in the film landscape who appear completely invulnerable to suspicion or romantic misunderstanding (when found in compromising positions, they usually just make a witty remark and find a cocktail). Virtually every other pair of comedy lovers of the period find themselves torn asunder by problems that could be solved if they just sat down and had an honest discussion.

Cary Grant and Irene Dunne tend to play these problems to perfection: Aside from The Awful Truth, they also show up in My Favorite Wife, in which Dunne's thought-to-be-dead character shows up after her husband Grant's second wedding and reveals she was merely stranded on a desert island (with, she conveniently forgets to mention, the enormously handsome Randolph Scott). Utter confusion is also the engine behind virtually every Fred Astaire-Ginger Rogers film, from The Gay Divorcee (in which Astaire is mistaken for a professional adulterer) to Top Hat (mistaken for a friend's husband). Of course, the films would be far less entertaining if everything was cleared up in the first act, but as relationships are not films, actually talking is made to seem like the best policy all round.

Healthy relationships are hard to come by, and harder still to maintain, but the lessons of bonkers romantic misunderstandings by gentlemen in top hats and enraged women in gowns rendered in black-and-white can still be valid. At the very least, showing Bringing Up Baby to my partner meant that he finally understood why I start laughing hysterically at the mention of leopards (watch it, you'll get it, too).