IT’S a slippery word, identity. We’re exploring it tonight in a talk at the Lyceum Theatre, as part of the Edinburgh International Science Festival. Our immediate topics are online identity, and your biological identity (Caryl Churchill’s stark play about cloning, A Number, is on after our discussion). But my prep has just sent the hornets whirling around my head.

When did this essentially philosophical term become part of our daily chatter? Google’s Ngram Viewer can chart the historical popularity of single words, using their massive corpus of scanned online books. It shows “identity” rising considerably through the 1960s, but taking a near vertical leap from the late 80s and early 90s, before beginning to tail off about 10 years ago.

For those who like to shout about (or at) what has come to be known as “identity politics”, this would all make perfect sense. If “my identity” means “who I feel I am, in relation to others I recognise and feel connected to”, then the rise of the counterculture, followed by the rise of hyper-consumerism, are exactly the conditions under which a politics of identity would flourish.

Think about how specific and constraining “my class” feels (and on the Ngram, “class” is almost a steady sine-wave). But you can actively construct, or seek out, your identity. The menu for identity has become enormous – chosen from the expanded range of social movements (along gender, race, language, nation), and from the vast menu of lifestyle signifiers (fashion, music, food, vocabulary). And all of this activity now turbo-charged by digital social networks. Yet we’re all aware that this “pick-and-mix”, multiple and flexible model of identity is now experiencing serious challenges.

There is much handwringing among the centre-left in UK, the US and Europe around identity at the moment. Many claim that Brexit and Trump show the peril in thinking that “progressive” electoral majorities can be built by piling up identity-based social groups, into a big, plural “us” (eg, Hillary Clinton’s “unloseable” election, made from women, blacks and Hispanics, the college-educated – all assumed to be “with her”). As these rainbow coalitions get constructed, are the more universal deprivations of economy and class left behind in their shadow? Those who defend identity politics often point out that these elements are not in opposition.

For example, Black Lives Matter – the movement that has sprung up around brutal police killings and mass incarceration of black people – also argues for reforms in tax and economics, education and universal healthcare. “Identity” and “class” are fused here. (I’d also say this fusion is sought, and sometimes achieved, in modern Scottish nationalism where recognising your “national identity” also implies achieving a social-democratic “good society”). It’s wrong, of course, to presume we could somehow separate a delightfully fluid culture of “online identity” from this street-corner struggle (#blacklivesmatter began life on Twitter, after all). One of the main vectors of recent populist politics – with even more to come – has been the construction of online identities.

Take the term “alt-right”, with its own symbolisms (Pepe Le Frog), its own hate vocabulary (“cucks”, “libtards”, “snowflake”), its own sub-charismatic figures (Milo Yiannopoulos, Richard Spencer), its own single-minded blogs (Breitbart).

The Patriotic Alliance, a political network funded and planned by former Ukip mogul Aaron Banks, will doubtless send out its own range of invitations to “identify” with the project. They’ve already nicked a Yesser meme to title their newsblog, “Wastemonster”.

And on that, let’s be honest: one way the indy movement maintained (and maintains) its attractiveness and mobilising powers is through being inventive and active with online identities. These identities are mostly uplifting, aspirational and positive, sometimes even operating as an alternative news service. But they also involve a lot of satiric meme-ing against our adversaries.

It can be rough-and-tumble play, for sure.

So we should banish any dreamy, early-2000s nostalgia about our cyberlives being entirely about the freedom to morph and splice our identities? The realities of power and money have barged into those fantasies. This is a terrain that all politics has to operate on. However, what is still fascinating about online identity is the way self-consciously created (and creative) personas permit you to be bigger, or stranger, than your official self. For example, it’s fun personally to tweet as @thoughtland, because the wordplay of the name invites me to try to live up to its concept. That is, to provoke and stimulate the minds of my 20,000-odd followers, who I presume are interested (at least) in the prospect of independence.

It’s also nice to tweet as @theplayethic, which allows another of my “identities” – as someone interested in play and creativity across the planet – to have its direct expression. I’d say the majority of us are involved in this banal, everyday practice of digital self-creation, at one level or other. We’re acutely aware of how we appear and what we select on our social media platforms. We’re all flexible and creative in this minor way.

But doesn’t this undercut the idea that “flexibility” and “creativity” are the loathed traits of those dreaded, haughty cosmopolitan city-dwellers – the pluralist “Anywheres”, intimidating the tradition-loving “Somewheres”, as David Goodhart puts it? Just saying. There might even be a politics here, indicating the complexity that exists beneath stated polarities.

One other caution. This might be an urgent debate about digitality and identity for us – we politics- and-culture anoraks of the Northern Hemisphere. However, the world contains more than us, and may have different priorities. For example, this year India is putting the final building blocks in place to establish a nationwide “identity” system called Aadhaar. It will be based on biometric information (retina scans and fingerprints), bank account details and other demographics.

Over here, the reaction to such a system (on both sides of the Tweed) would be a knee-jerk warning about 1984 or Brave New World. But many Indian commentators see it as the most extraordinary platform and opportunity to raise the skills, health and wealth of the continent.

They claim that this “national identifier” will enable reliability in the raising of taxes, the delivery of public services, the enforcing of business contracts and the availability of banking – extending way beyond India’s current middle-class bubble.

Other voices assert that the behaviour of the Indian state means they should not be trusted with the personal details of more than one billion citizens. But at the very least, this is “online identity” in a different mode. One put to the service of precision, efficiency and developmental goals, not free-wheeling self-creation.

Yet what if even this biometric identity – the uniqueness of a human retina – could be itself changed or morphed, as we face the coming era of gene editing and biological manipulation? The play that follows our talk tonight, Churchill’s A Number, is perhaps more concerned with cloning as an emotional test – shredding our sentimentality about parental responses – than as a coming reality. Nevertheless, that future is coming. Soon, parents will be able not just to delete inherited illnesses from the genomes of their children, but to consciously choose their talents, faculties, even personality. In that circumstance, exactly who (or what) would we be?

Our talk about online identity is a subset of a bigger concept of modern identity. This is identity understood as an achievement, a construction, an anchor consciously dropped into the seas of our lives. Yet bioscience drives us into a mind-spinning paradox. Our modernity also extends the frontiers of choice, going into places that trouble the very idea of “being human”. So how can we find the wisdom to choose not to choose?

To leave our beloveds alone to make their own futures, shape their own identities? And what kind of current “identity” – strung somewhere between hard science and moral genius – could help us make such a choice? Tonight, come and help us answer these questions.

Pat and Aleks Krotowski are talking about Online Identity at the Lyceum Theatre tonight, 7pm, before a performance of Caryl Churchill’s A Number, as part of the Edinburgh International Science Festival.