In 2016, in the wake of Brexit and the US election, Oxford Dictionaries named post-truth its Word of the Year — reporting a roughly twenty-fold spike in usage over the previous year.

Post-truth is not simply lying — lying is as old as speech. What is new is a public sphere where how a claim makes you feel, and whose side it signals, matter more than whether it is true.

Rumour, propaganda and demagoguery are ancient. What amplifies them now is infrastructure: smartphones in billions of pockets, algorithmic feeds, group chats and an economy that pays for attention.

With hundreds of millions of new, mobile-first internet users, dozens of languages and dense kinship and faith networks, South Asia is where post-truth dynamics play out at their largest human scale — often with life-and-death stakes.

Lumping everything together as 'fake news' hides what matters: was it meant to deceive, and was it meant to harm? Those two questions sort the field into three useful categories.

Disinformation is engineered. It is seeded by actors who know it is false and design it to exploit a fault line — a communal tension, an election, a fear.

Satire is legitimate — until it is screenshotted, stripped of its source and reshared as fact. Then a parody headline becomes, in effect, misinformation by accident.

The same study found false stories were markedly more novel than true ones, and inspired more surprise and disgust. Truth is often dull; lies can be tailored to be thrilling.

Bots rarely persuade you directly. Their job is to amplify — to make a fringe view trend, so that real humans assume it is mainstream and pass it on.

Pariser's worry: personalisation creates a unique universe of information for each of us, and we rarely notice what has been filtered away.

Echo chambers begin in human nature. We befriend, follow and marry within our groups — so our information diet is already narrow when the platform starts personalising it.

Honesty check: some researchers find the average person's online diet is more varied than the strong 'sealed bubble' story suggests, and that incidental exposure to other views still happens.

Falsehood succeeds partly because of how human cognition works. We are pattern-seekers and tribe-members first, dispassionate evaluators of evidence a distant second. These are features, not bugs — and they can be exploited.

The unsettling finding: more knowledge and numeracy can make this worse, because the clever are better at building arguments for whatever their group already believes.

An influential idea held that correcting a falsehood can strengthen belief in it — the so-called backfire effect. The story spread widely among communicators.

Combined with motivated reasoning, this breeds the loud, unshakeable confidence that travels so well online — while genuine experts hedge, qualify and lose the room.

Freud's nephew Edward Bernays fused psychoanalysis with publicity to found modern public relations. His 1928 book was titled, without embarrassment, Propaganda.

Bernays' insight was to appeal not to reason but to desire and identity — famously rebranding cigarettes for women as 'torches of freedom'. He sold the feeling, and the product followed.

Edward Herman and Noam Chomsky argued that mass media in market societies don't need overt censorship to serve power. Structural filters shape the news before it reaches you.

'Tax relief' versus 'tax cuts for the rich.' 'Migrants' versus 'refugees.' Same facts, different worlds. The frame does the persuading before the argument begins.

Classic propaganda pushed one consistent message. A newer tactic — the firehose of falsehood — floods the zone with many contradictory claims, fast and shameless, to exhaust and confuse rather than convince.

This is the crucial, uncomfortable point: an engagement-driven system can degrade public truth as a side-effect, with no villain intending it. The incentive does the damage automatically.

Because attention is money, creators learn what the algorithm rewards and feed it: sharper takes, scarier thumbnails, surer claims. The platform's incentive becomes the publisher's, then the public's.

For a century, a photograph or recording was strong evidence. Synthetic media — content created or altered by software — is dissolving that trust, at falling cost and rising quality.

The cheapest synthetic format needs no AI: a website built to look like a real news outlet — logo, masthead, datelines — publishing invented stories for clicks or influence.

The single most common visual falsehood in South Asia: a genuine image or video, stripped of its true context and recaptioned to inflame — an old riot, a foreign accident, a film scene, sold as today's local event.

Voice clones now need only seconds of audio; face-swaps run on consumer hardware. The frontier risks: fake statements by leaders, and non-consensual intimate imagery used to silence women.

Generative AI can now produce fluent text, images and voices in any language, instantly and almost free. It can write a thousand unique, native-sounding fake comments in the time it took to write one.

Its markers: I wouldn't want my child to marry one of them; I assume the worst of their motives; I believe bad news about them without checking.

Humans form group identities effortlessly — and once a line is drawn, we favour the in-group and suspect the out-group automatically. Politics, religion and caste supply ready-made lines.

Post-truth dynamics are sometimes dismissed as a distraction for the well-connected. In South Asia they shape whether children get vaccinated, whether riots ignite, and whether elections are trusted.

Health programmes live or die on trust. Rumours — that a polio or COVID vaccine causes harm or infertility — have stalled campaigns and cost lives, sometimes triggering attacks on health workers.

Across South Asia, false rumours — of child-kidnappers, cattle theft or blasphemy — spread through messaging apps have led to mob lynchings of innocent people, often strangers in the wrong place.

Coordinated falsehood — doctored clips, recaptioned images, fabricated 'crimes' — is repeatedly used to inflame communal and religious hatred and to scapegoat minorities.

On climate, tobacco and pollution, a recurring playbook manufactures doubt: not denying outright, but amplifying uncertainty to delay action — 'the science isn't settled'.

The deepest cost is corrosive and cumulative: when people trust no institution — not science, not the courts, not the press — cooperation on any shared problem becomes almost impossible.

We will never catch every lie. The realistic aim is resilience: people and communities harder to fool, quicker to check, and slower to spread — a population with cognitive antibodies.

Professional fact-checkers verify claims and publish corrections. South Asia has a strong, growing ecosystem of them — a vital public good.

Vertical reading (staying on the page, judging its slick design) is how the gullible are fooled. Leave the page to find out who is really behind it.

The most durable defence is widespread media and information literacy (MIL) — teaching people, from school age up, to source, verify, contextualise and question what they consume and share.