Illustration: a dossier collage of an intelligence briefing room with case files and behavioral-analysis notes on a chalkboard.

The research

The psychology of persuasion

Why these techniques work: the research on attention, memory, emotion, identity and belief that explains how a message gets past reasoned evaluation.

Illustration, not an archive object

The archive shows what propaganda looks like. This library explains why it works. Each page takes one well-studied feature of human thinking, sets out what the research actually found, says plainly how well that finding has held up, and shows how political messaging on every side has used it.

The pages are written for three kinds of reader: someone who wants to recognise manipulation when they meet it, someone studying the history in this archive, and someone writing political material of their own who wants to persuade honestly. They explain mechanisms so they can be understood and spotted. They are not instructions for deceiving people.

'Join us in a victory job' (Australian Department of National Service)

Kreuzburg O.S. 25-pfennig note: "97% für Deutschland!" (Upper Silesia, 1921)

Start here: the courseTake the courseTen short lessons on the basic techniques, one step at a time: what each one is, how it works, three real examples from different sides and eras, a check question and a spot-the-technique exercise on an archive object.

The three areas

The pages below are grouped into three areas: cognitive biases and heuristics, group identity, and emotion and fear. Each area has its own overview page, listed first in its group.

AreaCognitive biases and heuristicsHeuristics are rules of thumb: judging how likely something is by how easily examples come to mind, starting from the first number heard, trusting what feels familiar. They usually serve people well, which is why they…

Varokaa! Vakoilija! (Beware! Spy!): Finnish Winter War poster

AreaEmotion and fearEmotion is not the opposite of judgment; it is part of how people decide what matters and what to do about it. Messages that make audiences afraid, angry, disgusted, hopeful or nostalgic can inform or mislead depending…

Eesti rahwas, hoia kokku! (Estonian people, hold together!): Rahvarinne election leaflet

AreaGroup identityPeople are social animals, and much of what they believe arrives through the groups they belong to. Group membership shapes whom people trust, how they read evidence, what they are willing to say aloud and what they…

Cognitive biases and heuristics

Cognitive biases and heuristics
Heuristics are rules of thumb: judging how likely something is by how easily examples come to mind, starting from the first number heard, trusting what feels familiar. They usually serve people well, which is why they…
Anchoring Evidence: strong
Anchoring is the tendency for a number encountered first to pull later estimates toward it, even when the number is arbitrary. People start from the anchor and adjust, but usually not far enough. In politics, the first…
Availability heuristic Evidence: moderate
The availability heuristic is the habit of judging how common or likely something is by how easily examples come to mind. It is often a sensible shortcut, since frequent things are usually easy to recall. It misleads…
Base-rate neglect Evidence: strong
A base rate is how common something is in the first place: how many people have a disease, how many travelers are smugglers, how many deaths come from a given cause. Base-rate neglect is the tendency to judge a case by…
Confirmation bias Evidence: strong
Confirmation bias is the tendency to seek, notice, interpret and remember information in ways that fit what one already believes. It works at every stage: which questions get asked, which sources get read, how ambiguous…
Continued influence effect Evidence: strong
Once people have heard a claim, a later correction reduces its influence but usually does not erase it. People can remember and accept the correction and still lean on the false detail when they explain events or make…
Framing effect Evidence: strong
A framing effect occurs when the way a choice or issue is presented changes people's judgments, even though the underlying facts are the same or nearly so. Researchers distinguish two kinds. Equivalence framing…
Illusory truth effect Evidence: strong
The illusory truth effect is the finding that people rate statements as more likely to be true after they have encountered them before. Repetition makes a claim easier to process, and that ease is mistaken for a sign of…
Motivated reasoning Evidence: moderate
Motivated reasoning is the tendency to evaluate evidence by whether its conclusion is welcome rather than by its quality. People hold congenial claims to a lenient standard and uncongenial ones to a strict standard,…
Negativity bias Evidence: strong
People give more attention and weight to bad news, threats and losses than to good news, safety and gains of the same size. A single negative fact about a candidate, a product or a group can outweigh several positive…
Priming Evidence: mixed
"Priming" names several different ideas, and they have very different track records. In the narrow sense, seeing one word makes related words easier to recognize for a moment, which is well established. In the broad…

Emotion and fear

Emotion and fear
Emotion is not the opposite of judgment; it is part of how people decide what matters and what to do about it. Messages that make audiences afraid, angry, disgusted, hopeful or nostalgic can inform or mislead depending…
Affect heuristic Evidence: moderate
People often judge risks and benefits by consulting a quick feeling of good or bad about the thing in question. If they like it, they tend to see it as both beneficial and safe; if they dislike it, as both risky and…
Disgust Evidence: mixed
Disgust is the emotion of rejection: it makes people want to avoid, expel or stay clean of something. It evolved around food and disease but extends to people and behavior seen as contaminating. Propaganda has used it…
Emotional contagion Evidence: moderate
People tend to catch the moods of those around them: they mirror faces, voices and postures, and their own feelings can drift toward what they see. Face-to-face mimicry is well documented. Emotion spreading through…
Fear messaging Evidence: strong
A fear appeal is a message that tries to change what people think or do by showing them a threat. The research finds that fear appeals usually work, and work best when the threat is paired with a clear, believable…
Hope appeals Evidence: mixed
A hope appeal tries to move people by showing them a better future that is possible but not guaranteed, and a path to it. Campaigns across the political spectrum rely on hope at least as much as on fear. The research…
Identifiable victim effect Evidence: mixed
A single, named, pictured person in trouble tends to move people more than a large number of anonymous victims. Research has documented this, and the related finding that concern can fall as numbers rise. The effect is…
Moral outrage Evidence: mixed
Moral outrage is anger at someone who is seen to have broken a moral rule, combined with a wish to see them blamed or punished. It spreads well: people share it, reward it and are rewarded for expressing it. On social…
Narrative transportation Evidence: moderate
When people become absorbed in a story, they tend to come away holding beliefs that fit it, and while absorbed they argue back less. Psychologists call this absorption "transportation." It works for fiction as well as…
Nostalgia Evidence: moderate
Nostalgia is a sentimental longing for the past. For individuals it is mostly a pleasant, comforting emotion that people turn to when they feel lonely or uncertain. When it is shared by a group, as longing for a…

Group identity

Group identity
People are social animals, and much of what they believe arrives through the groups they belong to. Group membership shapes whom people trust, how they read evidence, what they are willing to say aloud and what they…
Conformity Evidence: strong
People sometimes go along with a unanimous group even when the group is plainly wrong, either because they start to doubt themselves or because they do not want to stand out. Solomon Asch's line-judgment experiments are…
Dehumanization Evidence: moderate
Dehumanization means seeing or portraying other people as less than fully human: as animals, vermin, disease, machines or monsters. Surveys find that a surprising number of people will openly rate some groups as less…
Group polarization Evidence: strong
When people who already lean the same way discuss an issue together, they tend to come out leaning further in that direction than when they went in. Liberals who talk with liberals become more liberal; conservatives who…
In-group favoritism Evidence: strong
People tend to treat members of their own group better than outsiders: they trust them more, give them more, and judge them more generously. The effect appears even for groups created on the spot, and it is strong for…
Moral foundations Evidence: mixed
Moral foundations theory proposes that people build their moral judgments on a handful of intuitive concerns, such as preventing harm, fairness, loyalty, respect for authority and purity, and that political groups…
Obedience to authority Evidence: moderate
In Stanley Milgram's experiments of the early 1960s, most ordinary volunteers kept giving what they believed were painful electric shocks to a stranger because a researcher told them to continue. Partial replications…
Out-group homogeneity Evidence: moderate
People tend to see members of other groups as more alike than members of their own: "we" are a varied bunch of individuals, "they" are all the same. This makes it easier to generalize from one outsider's behavior to the…
Pluralistic ignorance Evidence: moderate
Pluralistic ignorance is when most members of a group privately reject a view or practice but each wrongly assumes that most others accept it. Because everyone reads the public silence or public conformity of others as…
Social identity Evidence: strong
Part of who people think they are comes from the groups they belong to: nation, faith, class, region, party. Laboratory work since 1970 shows that even a meaningless label is enough to make people favor "their" side.…
Social proof Evidence: moderate
When people are unsure what to think or do, they look at what others around them are doing and treat it as evidence. Researchers call information about what most people actually do a "descriptive norm." Messages that…

Countering propaganda

Countering propaganda
What has been tried against propaganda and disinformation, who tried it, and what the measured effects were, including null results, backfire findings and the criticism each approach drew from across the spectrum.
The debate over counter-disinformation Evidence: mixed
The arguments cover the whole toolkit: government contacts with platforms, platform removals and labels, academic monitoring, and state bodies such as the global-engagement-center, the…
Fact-checking and corrections Evidence: moderate
Inoculation and prebunking Evidence: mixed
William J. McGuire and his Yale collaborator Demetrios Papageorgis set out the idea in experiments published between 1961 and 1964, including papers in Sociometry and the Journal of Abnormal and Social Psychology (1961)…
Media literacy Evidence: mixed
Organised teaching about propaganda in the United States goes back at least to the institute-for-propaganda-analysis (1937 to 1942), founded at Columbia University's Teachers College by Clyde R. Miller, Kirtley Mather…
Platform interventions: labels, nudges, notes, friction and takedowns Evidence: mixed

Basics

Cold War propaganda: US and Soviet posters, radio and leaflets
Cold War propaganda was the persuasion and disinformation that the United States and the Soviet Union, with their allies and clients, aimed at foreign publics, at each other's populations and at their own from about…
Propaganda, misinformation and disinformation: the differences
The three words are often used as if they meant the same thing. In the research literature, misinformation and disinformation describe content (false or misleading) and differ by intent. Propaganda describes a method of…
The big lie: where the term comes from and how it is used
"The big lie" is an English rendering of die große Lüge. It first appears in print in Adolf Hitler's Mein Kampf (1925), where Hitler uses it as an accusation against others: he says that Jews and Marxists blamed General…
What is propaganda? Definition, history and examples
Propaganda is communication designed to shape what an audience believes or does by working on emotion, identity, authority, repetition or omission, instead of offering a claim that can be checked. The word began as the…
WWI propaganda posters: who made them and how they worked
Every major belligerent used posters in the First World War, mostly for three jobs: recruiting soldiers, selling war bonds, and shaping conduct on the home front. The institutions differed. The United States ran a…
WWII propaganda: posters, radio and film by every side
Every major belligerent of 1939 to 1945 ran organised propaganda through posters, newsreels, film, radio and leaflets. The methods overlapped: fear of the enemy, unity slogans, secrecy warnings and appeals to sacrifice.…

How we rate the evidence
Psychology has changed a great deal since the early 2010s. Large, coordinated attempts to repeat well-known experiments found that many published effects were smaller than first reported, and some did not appear at all.…