One evening last week, I stood at the front door of an old friend’s place in my best coat, clutching a bottle of supermarket champagne. From inside I could hear voices in the hallway, the rustle of scarves being unwound and coats shrugged off, a blast of music as the kitchen door opened and closed. My hand hovered over the doorbell, then hesitated, smoothed my hair. An alternative vision of the evening – sofa, family, dog, perhaps another episode of Fisk on Netflix – slid unbidden into my mind. Anxiety spiked. Had my hair gone flat? What’s the host’s new girlfriend’s name again? Do I even remember how to behave at parties?

Parties are the very last garrison of the pre-digital world. Almost every other facet of our lives has been changed beyond all recognition by the internet. We work from home instead of the office, we buy groceries on our phones instead of pushing a trolley around the aisles. Networking, keeping up with friends, dating, flirting, even the way we have sex. Everything is different, except for parties, which are exactly the same as they always were: a roulette wheel of human-on-human interaction, with no screens to hide behind.

We are a little bit scared of parties, these days. Covid has left us with a lingering sense of other people as somehow unclean. There is no way back, now, to the innocence of the pre-2020 era, when we lived in blissful ignorance of the fact that the birthday girl was spraying a fine mist of germs over her cake when she blew out her candles. The Partygate scandal contaminated the idea of parties, casting them as something that the bad guys do. The rise of hygge as a lifestyle fantasy has given us a new vision of aspirational winter living that celebrates cosy socks and sipping warm drinks from a favourite mug, possibly in an isolated log cabin. Personal space has become a lonely little hill we are prepared to die on.

But parties are not selfish: they are generous. Partying is not just hedonism; it is a positive thing that we do together and for each other. There is, in fact, an evolutionary argument for your festive shindig. Early human beings were greatly outnumbered by other animals, and to survive we needed to bond. The rituals of togetherness developed as a kind of social technology, rewiring our brains along collective lines. Nick Hopkins, a professor of social psychology at the University of Dundee who has studied the impact of collective participation on social identity, told an interviewer that celebrating as a group “transforms our experience of a crowd. It’s no longer just an aggregate of individuals – it is something more than that.” Instead of thinking about yourself as “me” and the rest of the people as “them”, you come to think of “us”. The term “collective effervescence” was coined by the French sociologist Émile Durkheim in 1912, to describe the energy and sense of harmony that occurs when people come together to share an experience. That happens in religious contexts, but also on a dancefloor, in a football stadium, singing happy birthday in a crowded kitchen. Collective activity triggers a euphoric response, unleashing a mental elixir that unites everyone who lived the moment together. Durkheim described collective effervescence as “a sort of electricity”, which, he argued, fundamentally changed our consciousness. Sharing a celebration or a ritual stimulates the social part of our brain, making individual concerns seem less important and shared ones feel more important. Partying together strengthens the bonds of community and society.

I know what you’re thinking. It’s all right for her: she’s probably one of those extroverts. I’m not sure I am, actually, although it helps that I like getting dressed up, because once you’re dressed to go to a party you’re halfway there, in effort and mindset. But being an introvert doesn’t mean you don’t need social connection; it just means that you tend not to seek it out. (The assumption that introverts were in their element during lockdown was proved wrong in the pandemic, when it was introverts, not extroverts, who reported more depression, anxiety, stress and loneliness. When your “social battery” is running on empty, it is being around other people, not a night alone scrolling your phone in front of the TV, that will recharge it.

Two years ago, the fashion writer Leandra Medine Cohen told a story in her newsletter that has stayed in my mind ever since. She was at a party and, having intuited a casual vibe from the lack of explicit dress code, was wearing jeans and a white T-shirt, when “a close friend walked in wearing a fire-engine-red dress that hit just above her ankle with sheer black tights and lace-up stiletto sandals … in my head, I went thank you – like got grateful to the friend … for reminding me what it looks like to suspend self-doubt.”

The suspension of self-doubt gets to the core of why a party can fill you with terror in advance and then turn out to make your heart sing. Yes, parties are intimidating. Someone might ask you a question when you’ve just taken a bite of mince pie. You might drink too much and dance badly. But here’s the thing: research has shown that we tend to expect interaction with people we don’t know well to be more stressful than it actually is when we experience it. It is a matter of empirical evidence, in other words, that you will tend to have more fun than you think you will.

You can tell that we know, deep down, that parties matter, from the way they loom large in our culture. The work Christmas party has taken its place in the canon of great festive traditions, along with stir-up Sunday and Carols from King’s. Step inside any clothes store at any point this month, and you will find yourself in a world of sequined dresses and shiny party shirts. The bandwidth taken up in shop windows and advertisements – and, for many of us (Me! Hi!), in our wardrobes – by clothes-to-wear-to-parties is out of all proportion to the amount of time that most of us actually spend at said parties, compared with, say, at work, or looking after kids. We are bewitched by the fantasy of parties, even if hesitant when it comes to actually pressing the doorbell. The word glamour comes from “glamer”, which in early 18th-century Scots meant “a magic spell”.

It seems to me that we could do with a bit of magic, right now. Parties may have been part of the problem in the era of social distancing, but now they can be part of a solution. Parties can strengthen our frayed synapses of community and commonality. The world has probably never felt more divided into opposing sides than it does now. At a party we can imagine ourselves all in it together, at least for a couple of hours.

I rang the doorbell, put on my best smile, hoisted the bottle in greeting. The door opened. And when it closed behind me, we were all on the same side.

Further reading

Why Has Nobody Told Me This Before? by Dr Julie Smith (Penguin, £16.99)

Mrs Dalloway by Virginia Woolf (HarperCollins, £7.99)

The Great Gatsby by F Scott Fitzgerald (Alma, £4.99)