If you’re an activist working on causes like animal rights, climate justice, or social inequality, things can sometimes feel stagnant and hopeless. People seem indifferent, the public space feels silent, and in the midst of that indifference, it can be hard to believe that change could happen at all. But as Cass Sunstein explains in his book How Change Happens and in his interview on the 80,000 Hours Podcast (which inspired this post) that silence doesn’t always mean there’s no hope. In fact, many of history’s major transformations began in moments that seemed just as “quiet.”
Sunstein is a well-known scholar in behavioral science, law, and policy. He served in the White House during the Obama administration and is the co-author of widely influential book Nudge. He has also written extensively on animal law and rights, publishing influential legal essays such as “The Rights of Animals: A Very Short Primer,” and “Standing for Animals”.
In his book How Change Happens, however, (which we take a closer look at in this post) he examines why major social transformations so often unfold in unexpected ways. He points to events such as the the Iranian Revolution, the collapse of the Soviet Union, the Arab Spring, or #MeToo, all of which surprised not only the public but also the leaders and experts of their time. ‘‘Lenin himself admitted he could hardly believe the speed of the Russian Revolution, and many participants in the Iranian Revolution said they never anticipated such a profound shift’’ he says. He also recalls that the Arab Spring coincided with his time in the White House, and even the most knowledgeable experts at the time failed to predict how events would unfold.
And it’s not just major political upheavals, norm shifts that seem “everyday,” like smoking bans, can also happen with surprising speed. Not long ago, smoking in restaurants, airplanes, and even hospitals was completely normal, yet in a relatively short time it became something society not only frowned upon but actively disapproved of.
So, what drives these changes that seem to happen all of a sudden? Understanding the factors that make seemingly unexpected shifts possible can help us steer the movements we’re part of today in a more deliberate and effective way. That’s why, in this post, we’ll look at the three key mechanisms Cass Sunstein offers in response to this question, and end the post by discussing what strategic lessons animal advocates can draw from Sunstein’s work.
Why does change happen suddenly and unexpectedly?
Long story short: what looks “sudden” is usually the moment hidden opinions surface, enough people cross their personal thresholds, and influence cascades through social ties.
According to Sunstein, these three interacting dynamics drive social change like this:
First, people don’t always say what they really think: fear of backlash or isolation keeps them quiet, making views that do exist look absent from the outside,and this silence is hard to measure, even with surveys.
Second, everyone has a different “action threshold”: some jump in at the first spark, others move only after seeing enough people do the same, and a person’s true threshold is hard to know,even to themselves.
Third, we’re strongly shaped by our surroundings: what others say, think, and do informs what we see as reasonable or acceptable, yet who influences whom, when, and how a message will resonate is inherently unpredictable.
Taken together, hidden preferences, unknown thresholds, and unpredictable interactions make social change hard to forecast which make it looks “sudden” and “unexpected.”
So let’s take a closer look at each of these factors to better understand how they work and what they mean for driving meaningful change.
1-) Preference Falsification: People Hide What They Really Think (and It’s hard to measure)
Sunstein calls the tendency for people to hide (or distort) their true beliefs “preference falsification.” Someone who actually dislikes the status quo might still say they’re fine with it, change the subject when it comes up, or deliberately turn down the inner voice saying, “this isn’t right.” The main reason is fear; fear of punishment, exclusion, ridicule, or being left out. (Here, Sunstein points out that social norms can sometimes be even more powerful than the law.) This is why, from the outside, it can look like everyone is on the same page, when in reality very different thoughts may be circulating beneath the surface. He quotes a former Nazi who put it bluntly: “How can you know what someone is against? It depends on to whom, when, and how they say it.” In other words, what people express depends heavily on the setting and the norms in play.
This leads us to the concept of pluralistic ignorance: people in a society often misjudge what others actually think. Everyone might assume that others support the status quo, when in fact many are uncomfortable with it but remain silent. In this context, Sunstein shares a striking example from his book about young men in Saudi Arabia: most privately had no problem with their wives working, yet they stayed quiet because they believed other men were opposed. When researchers told them, “Actually, most people think like you do,” within a few months the number of women applying for jobs increased. In other words, when hidden views become visible, behavior can change quickly. But measuring these hidden beliefs ,knowing who truly thinks what and when they might speak up, is extremely difficult.
2-) Action Thresholds: Everyone’s Threshold for Taking Action Is Different (and it’s even harder to predict)
To explain social change, Sunstein uses a model he calls “action thresholds.” Each person has a different level of social support they need before joining a movement or speaking up, that’s their action threshold. Two people may feel equally troubled by the same issue, yet they won’t necessarily act at the same time; one may have a lower threshold, while the other needs to see much more support before stepping in.
Sunstein illustrates this with a personal story: years ago, while walking with a friend, he saw a father hitting his child in the street. Without hesitation, his friend ran up to the man and shouted, “Stop hitting that child!” This is a classic example of a low threshold, acting without waiting for anyone else’s support. Sunstein, on the other hand, only followed and backed him up afterward, his own threshold was a bit higher. For some people, taking action against injustice requires far more “pre-signals” before they step in.
Sunstein describes these different thresholds using a kind of number sequence: some people will act without seeing any approval from others, he calls them “zeros.” Zeros are the ones who light the first spark; they might be brave, reckless, or simply very determined. (What’s striking is that these low-threshold individuals can appear in all kinds of causes, they might start a fight for freedom, but they can just as easily be the first champions of an authoritarian or discriminatory movement.) Next come the “ones,” who will act only after seeing at least one person go first. “Twos” want to see two people, “threes” need three, and so on, up to “tens,” “hundreds,” or “thousands.” Each new person looks to those who came before them, seeking a kind of “confidence threshold.” At the far end of the spectrum are the “infinities,” who, no matter how much support they see around them, will never speak out against the status quo.
The key point here in explaining why social change can seem so unpredictable is that, just as preference falsification hides people’s true opinions, action thresholds are usually invisible as well. A person may not even know their own threshold. Sunstein gives an example from the Iranian Revolution: many who took part later said they were surprised at how far they had gone. Someone who thought of themselves as a “seventy” found, under the influence of the moment, that they behaved like a “four.” Others who believed they would never take action ,that they were “infinities”, suddenly found themselves out on the streets.
3-) Interdependences and Social Influence: We All Look to What Others Are Doing (but interactions are highly unpredictable)
Another key factor in Cass Sunstein’s analysis is that individuals influence one another far more strongly than we might think. What we choose to believe, what we decide to support, and even when we choose to speak up all depend on the people around us. And these individual influences can cascade, producing large-scale social consequences.
Sunstein explains this through the concept of interdependences: Who did what? Who saw it? When did it happen? Each of these factors can determine whether someone else crosses their threshold and takes action. For example, a “zero” , someone who takes the first step without waiting for approval, will have no impact if their act goes unnoticed. But if that same person speaks up at the right time, in the right place, and in front of the right people, they can pull the “ones” and “twos” in behind them.
This interdependence makes social change especially hard to predict, because the timing and impact of interactions are often a matter of chance. Sometimes a single moment, overhearing a sentence on the street, stumbling across a video on social media, or a friend quietly saying, “I feel the same way”, can be enough to lower someone’s action threshold. But we can never know in advance which interaction, at what moment, will have that effect on whom.
Strategic Takeaways for Animal Advocacy
So, how can we use these insights about how social change works to draw strategic lessons for animal advocacy? As Sunstein points out, when we better understand mechanisms like preference falsification, varying action thresholds, and interdependences, we gain powerful clues for how to spark and grow a movement. With that in mind, let’s look at five ways we can apply these factors to strengthen animal advocacy.
1-) Silence Can Be Misleading
Preference falsification tells us this: silence doesn’t mean no one cares. People often hide their true feelings out of fear of backlash, of being told they’re “overreacting,” or of ending up isolated. This means far more people may be uncomfortable with industrial animal farming than we think; but if no one around them is speaking up about it, they may stay quiet or passive.
What Do the Surveys Say?
In fact, national surveys in the United States show that most people believe it is “very important” (52%) or “important” (32%) to prevent farm animals from suffering (Animal Welfare Institute). Data from the Center for a Livable Future shows that 57% of voters support stricter regulation of industrial farms, and 43% support banning new ones altogether. Given that the share of vegans in the total population is still very small, these findings are striking. This suggests there’s far more potential than we might assume, but perhaps not enough “thresholds” have been crossed yet for these views to turn into action.
One takeaway from this could be that the situation isn’t as hopeless as it might seem, and once certain steps are taken, change could happen much faster than we expect. This understanding can also keep us from falling into the mindset of “nobody cares anyway,” helping us stay hopeful and providing strong motivation to act strategically.
2-) Someone Has to Go First
Sunstein’s “action thresholds” model shows that for the silent majority to start moving, someone has to make the first move. Without that first person or group stepping forward, the chain reaction never begins. This should give us a strong motivation to speak out more boldly in different contexts: if no one starts, no one else can follow.
In the field of animal rights as well, many pivotal moments began this way: the first voices to speak openly about animal exploitation, the first undercover videos released, the first major corporate commitments, the first plant-based products to achieve unexpected sales success, the first time chain restaurants added permanent vegan options to their menus… All of these “firsts” sent the same message to people: “ The change is not as impossible as it seemed.”
What’s more, steps like these can shift the perspective not only of the public but also of decision-makers; what was seen as “too radical” yesterday can become reasonable, even standard, today. That’s why we shouldn’t hesitate to create the same effect in different settings: whether we’re transforming a university cafeteria menu, working to include plant-based options in a municipality’s catering contract, calling out a flawed practice within the movement, or championing a method no one around us has tried but we believe will work… Wherever a small “first” is possible, creating a visible starting point there can lower the action threshold for thousands of people.
Note: At this point, there’s an important caveat; being the first requires not only courage but also strategy. The method and credibility of that first voice can lower action thresholds, but it can just as easily raise them or block them altogether.
Stop Huntingdon Animal Cruelty (SHAC) is a clear example of this slowing effect. Founded in the UK in 1999, SHAC aimed to shut down Huntingdon Life Sciences, one of the world’s largest animal testing laboratories. At first, they ran a strong campaign: pressuring companies that worked with the lab, organizing consumer boycotts, holding protests… But over time, their tactics shifted: sending threatening letters to company employees’ homes, causing property damage, physical assaults. Such actions were framed by the broader public not as a “just cause” but as “terrorism.
” The result? In 2006, the Animal Enterprise Terrorism Act (AETA) was passed in the US, and the UK introduced strict security laws and special protections for companies. The movement was both criminalized and stripped of legitimacy. Some corporations and media outlets used these incidents to reinforce the narrative that “animal advocates are extreme and dangerous,” which in turn raised the action thresholds of both the public and decision-makers.
Our takeaway here is that the animal movement needs to become much more visible and bold across many areas. However, when taking that “first” step, it’s crucial to ask ourselves: will this move lower other people’s action thresholds, or will it raise them?
3-) Different Thresholds Call for Different Approaches
Another lesson we can draw from the idea of action thresholds is that expecting everyone to respond to our message at the same pace doesn’t match how social change actually unfolds. This is why we need a step-by-step outreach strategy that takes these thresholds seriously.
Our methods should be designed to appeal to people at different points along the spectrum. For example, someone with a very high threshold might not change their life after hearing a single talk on veganism; they may first need to see more people in their own circles adopting it. Still, that same person might support our efforts to increase plant-based options in their institution or back a campaign we run against animal testing.
This means that by recognizing different thresholds and diversifying our approaches, we can bring more people into the process without losing those who could potentially support the animal movement — and in doing so, we can accelerate change.
4-) The “More and More People…” Effect
One point Sunstein repeats several times in his 80,000 Hours podcast interview is that people decide what they see as “reasonable” based on those around them. For us, this means that if we want to create behavior change on an issue, making the action in question feel normal is both incredibly effective and, for many people, necessary. Here, Sunstein highlights the importance of dynamic norm messages, messages that emphasize more and more people are adopting a certain behavior, and adds that this isn’t just an intuitive claim; it’s backed by behavioral science research.
How Do Dynamic Norm Messages Work?
In a 2017 study by Gregg Sparkman and Gregory Walton at Stanford, participants who were told that “more and more people are reducing their meat consumption” showed greater behavior change than those who only received an “ethical appeal.” The researchers explained this effect with two factors: (1) People are sensitive to the “direction of the trend” , they want to adopt today what they believe will be widespread in the future. (2) The social risk decreases, the feeling of “I’m not alone; others are moving in this direction too” lowers the action threshold.
The same approach has also worked in areas like energy conservation (Schultz et al., 2007), tax payment rates (Hallsworth et al., 2017), and hotel towel reuse (Goldstein et al., 2008): messages such as “Most of your neighbors are saving energy,” “Most people pay their taxes on time,” and “The majority of guests reuse their towels” have each been shown to be highly effective.
The common thread in all these examples is this: people aren’t convinced just by hearing what’s “right” , they need to see what others are actually doing. They come to see a new behavior as “reasonable” when they notice that more and more people, from a growing range of backgrounds, are adopting it. In animal advocacy, we should make these kinds of data points, stories, and “firsts” more visible: dynamic norm messages like “More people are trying plant-based products every year,” “X number of cities have changed default menus in public institutions,” or “Company X has announced an animal welfare policy” can open doors far more quickly than moral arguments alone.
5-) Coming Together Lowers Thresholds
Another key point emphasized in the material is that when people realize there are others who share their concerns and values, they feel “I’m not alone”, and this can significantly lower their action threshold. That’s why collective spaces such as local meetups, online groups, student clubs, and campaign teams play a strategic role in a movement. When people come together, they boost each other’s courage, express their ideas more freely, and realize that issues they once felt were “too radical” or “only my concern” are actually shared by many others. This, in turn, encourages them to act more visibly, more effectively, and more consistently.
The example of the Chinese government given in the podcast also supports this point. Sunstein notes that understanding the processes of social change is used not only to start and grow a movement, but also to stop one. The Chinese state often allows complaints on social media, but deletes concrete calls to organize, such as “Let’s meet on this street on Thursday.” A visible gathering point can both break through preference falsification and trigger a chain reaction, so the government tries to prevent these “first sparks” from being seen in order to stop an outbreak from occurring.
Note: Just as with the example of “zeros” having the opposite effect, there’s another important point to watch for here: group polarization. While communities can help individuals feel less alone and lower their action thresholds, over time this togetherness can also carry the risk of closing in and losing touch with the outside world.
However, this side effect can be minimized through certain practices, intentionally making space for different viewpoints, doing “steelman” exercises to present opposing arguments in their strongest form, inviting outside speakers, and building a culture that regularly tests our own claims and strategies. This way, we can create supportive communities while maintaining the flexibility and openness needed to reach wider audiences without getting trapped in an echo chamber.
Conclusion
Sunstein’s framework reminds us that change often brews quietly beneath the surface until the right mix of visible voices, lowered thresholds, and reinforcing social influence tips it into motion. For animal advocates, this means recognizing the hidden potential that exists beyond what we can see, being strategic and intentional in how we create “firsts,” tailoring our approaches to different audiences, making progress visible through dynamic norms, and building communities that inspire action without closing in on themselves. By combining courage with strategy and paying attention to the social mechanics of change, we can help turn quiet undercurrents into powerful waves for animals.