Jordi Casamitjana, author of the book “Why Vegans Don’t”, looks deeply at how to deal with the problem of cognitive dissonance in relation to issues involving nonhuman animals
I had never heard it before.
One of the things that happens when you become vegan is that your vocabulary increases in size considerably. Not only you learn about all sorts of animal products that you did not know that existed (such as carmine or shellac), and find out about which terms should you be using to replace carnist euphemisms (such as Companion Animal instead of pet or pig flesh instead of pork), but you also learn new foundational terms about the nature of the issues you will now be constantly talking about.
One of such terms is “carnism” (the opposite of veganism), which I defined as “The prevailing ideology which, based on the notion of supremacy and dominion, conditions people to exploit other sentient beings for any purpose, and to participate in any cruel treatment of nonhuman animals. In dietary terms, it denotes the practice of consuming products derived wholly or partly from culturally selected nonhuman animals.” Another one is “animal exploitation”, which I define as “Any use of any sentient being for profit, social gain, ritual, leisure, work or subsistence in which that being is not a willing participant or has been physically or psychologically coerced to participate.” Another one is “ahimsa”, the ancient Sanskrit word that means “do not harm”, which constitutes the most important tenet of the philosophy of veganism.
An interesting one is “cognitive dissonance”. I must confess that I had never heard about it before I became vegan in January 2002. This one is interesting because it describes a psychological process that explains why people follow carnism rather than veganism even when exposed to the truth of animal exploitation, and why they only apply the principle of ahimsa in some circumstances involving some animals, but not others. This one has become familiar to many vegans who do vegan outreach, as they often have to refer to this concept when they detect certain attitudes or responses from strangers they are outreaching to. This one is very relevant because many vegans claim that they got rid of their cognitive dissonance when they became vegan, but they did not — they just shifted its application. I think this one deserves an article of its own, so we can discuss how to deal with it when it involves nonhuman animals.
What is “Cognitive Dissonance”
Cognitive dissonance is one of the most influential concepts in modern psychology, describing the distinctly human discomfort that arises when a person holds two or more contradictory beliefs, values, attitudes, or behaviours at the same time. This tension motivates people to change their thinking or justify their actions. The term was introduced in the late 1950s by the American social psychologist Leon Festinger, whose work was inspired in part by observing a doomsday cult whose prophecy failed to materialise. According to him, instead of abandoning their beliefs, many members strengthened them, rationalising the failure by claiming their collective faith had averted the disaster. This paradoxical reaction led Festinger to explore the human need for internal consistency, culminating in his 1957 book “A Theory of Cognitive Dissonance”, where he formally defined the concept.
Cognitive dissonance occurs whenever there is a clash between different parts of a person’s mental life — such as when someone’s behaviour contradicts their values, when two beliefs conflict, or when new information challenges an established worldview. A person who values health but smokes, or someone who sees themselves as compassionate while contributing to practices they know cause harm to sentient beings, experiences this internal conflict. To reduce the discomfort, people may change their beliefs, alter their behaviour, rationalise the inconsistency, or avoid information that intensifies the conflict.
The concept applies across many domains of daily life. In consumer behaviour, it emerges after major purchases when people seek reassurance that their decision was ethical. In social and group contexts, dissonance helps explain why individuals maintain loyalty to groups even when faced with contradictory evidence, since group belonging can outweigh the discomfort of inconsistency. Personal relationships also display clear examples, as individuals may justify harmful behaviour from loved ones to maintain a coherent emotional narrative. On a broader scale, cognitive dissonance plays a role in societal issues such as climate change and animal ethics, where people often hold values that conflict with their everyday choices.
Several theories attempt to explain why cognitive dissonance exists. Festinger’s original view treated it as a motivational drive similar to hunger, as an innate need for mental consistency that reduces the discomfort of contradiction and supports effective decision-making. Other psychologists have proposed that dissonance is tied to self-concept, arguing that it is strongest when inconsistencies threaten one’s sense of identity, such as the belief that one is honest or compassionate. Evolutionary explanations suggest that dissonance promotes psychological stability by encouraging people to commit to decisions, which may have supported cooperation and long-term planning in early human societies.
In essence, cognitive dissonance is a core psychological mechanism that profoundly shapes how people justify their actions, interpret new information, and maintain their identity. Therefore, it is central to understand veganism (a philosophy that makes people change their behaviour when they can no longer justify their actions, and which creates a new identity), but also to understand carnism (when people ignore the evidence of the wrongs of animal exploitation or do not want to hear arguments that expose their cognitive dissonance regarding how they treat different nonhuman animals (such as petting one type but eating another). Let’s dig a bit deeper into this.
Research on Cognitive Dissonance
Although no study has ever quantified the overall prevalence of cognitive dissonance, a substantial amount of research has measured how consistently it appears, how strongly people react to it, and how reliably it can be induced in controlled settings. Much of this evidence comes from human experiments beginning with Festinger and Carlsmith’s classic 1959 study, in which participants were asked to perform a dull task and then lie about its enjoyment for either one dollar or 20 dollars. The findings showed that those paid only one dollar experienced greater cognitive dissonance and subsequently altered their attitudes more strongly. Replication studies over many decades have confirmed that most participants display similar patterns when faced with contradictions between beliefs and actions.
Modern psychology has also produced quantitative summaries of this subject of research. Meta-analyses — such as those conducted by Eddie Harmon-Jones and colleagues in 1999 and later in 2015 — have statistically synthesised hundreds of studies across different cultures, experimental paradigms, and methodological designs. These analyses consistently reveal medium to large effect sizes, showing that dissonance-related behaviour occurs reliably in a wide range of situations. While such work does not measure how many people experience dissonance in daily life, it demonstrates that when dissonant conditions are created, the vast majority of individuals respond with predictable attempts to reduce psychological discomfort.
Neuroscientific research has added another layer of quantification. Functional MRI studies examining the brain’s response to contradiction and conflict show increased activity in regions such as the anterior cingulate cortex, which monitors cognitive conflict, and the prefrontal cortex, which is associated with emotional regulation and reappraisal. These neural responses occur in most participants exposed to dissonance-inducing situations.
Cross-cultural research further reinforces this conclusion. Studies conducted in countries across Asia, Europe, Africa, the Middle East, and the US show that cognitive dissonance appears in all populations tested, even though the specific triggers may differ. In Western cultures, dissonance tends to arise more strongly from personal inconsistency, whereas in many Eastern cultures it is more associated with failures to meet social expectations or group norms.
Therefore, it appears that cognitive dissonance is extremely common everywhere, highly predictable, and measurable through behavioural, statistical, and even neurological methods. We are going to find it not only in people whose indoctrination into carnism has transformed them into vegan deniers, vegan sceptics, or even veganphobes, but we are also going to find it in vegetarians and vegans (even those who label themselves as ethical vegans — as I do).
Cognitive Dissonance in Carnists
Let me first begin by saying that, for convenience, I will be using the term “carnist” to mean people who have been fully indoctrinated into the ideology of carnism and who still reject veganism. I do not mean it as a “type of human” different from vegans, because the immense majority of vegans had also been indoctrinated into carnism, but managed to remove part of that indoctrination to the point that now they consciously choose veganism to guide their lives. Therefore, most vegans were once carnists, and all carnists can become vegans — I sometimes call carnists “pre-vegans”, and this is why I don’t want to call them “non-vegans” in this article. I don’t see carnists as “bad people” or “wrong people”, but as human victims of carnism who should also be liberated as its nonhuman victims. However, labelling them as “carnists” in this article is a convenient way to express the narrative points I want to put across — but it should not be regarded as me “putting them down” or “devaluing” them.
Having clarified this, how does cognitive dissonance manifest in carnists? Cognitive dissonance is an essential component of carnism because carnism itself depends on maintaining contradictions. The ideology requires people to see themselves as compassionate, fair, and morally coherent while simultaneously participating in practices that cause profound harm to sentient beings. Most people heavily indoctrinated into carnism already hold the “animal welfare” values that would help move them toward veganism — they believe cruelty is wrong, they say animals should not suffer “unnecessarily”, and they recognise that some nonhuman animals can think, feel, and fear — yet they continue to consume their flesh, milk, and eggs. This gap between values and actions creates a significant amount of psychological tension, which carnism solves through a series of culturally normalised defence mechanisms designed to reduce dissonance without requiring behavioural change.
The most common of these mechanisms is the refusal to see certain animals as individuals. Carnism assigns different moral categories to different species, such as dogs are family but cows are commodities, or cats are companions but pigs are products. These contradictions are so deeply internalised that many people do not even register their inconsistency until it is pointed out to them. When vegans highlight these disparities, the carnist’s dissonance suddenly becomes conscious, and the person may respond with discomfort, irritation, humour, dismissal, or even hostility. That hostility is not a sign of inherent bad character; it is simply the mind defending itself against the discomfort of dissonance by rejecting the messenger rather than confronting the message.
Avoidance is another powerful dissonance-reduction strategy. Carnists may deliberately avoid information about slaughterhouses, transport trucks, hatcheries, dairy farms, zoos, or vivisection laboratories because they intuitively know that watching such footage would make their current habits indefensible. They may also avoid conversations with vegans, skip animal rights documentaries, or prefer euphemistic terms that distance them from the reality of who they are consuming (“pork” rather than pig flesh, or “beef” rather than cow flesh). This avoidance is not ignorance in the passive sense; it is an active, culturally reinforced strategy to reduce the discomfort of moral conflict.
Rationalisation plays an equally central role. Many carnists resolve their dissonance by appealing to tradition (“we’ve always eaten meat”), nature (“canines, though”), necessity (“we need protein”), or hierarchy (“animals are here for us”), even if their arguments are constantly debunked. None of these claims stands up to scrutiny, but they serve the psychological function of allowing individuals to maintain a positive self-image while continuing to participate in the exploitation of other animals. These rationalisations also have a social dimension, as carnists tend to reinforce one another’s justifications, collectively sustaining an ideology that benefits from being unquestioned.
Some carnists experience a deeper form of dissonance when they sense that their moral identity and their behaviour are not aligned. This can lead to defensiveness, sarcasm, accusations of vegan extremism, or attempts to frame vegans as judgmental — all of which are emotional shields protecting the fragile sense of self that carnism continuously destabilises. Ironically, the more compassionate a person is, the more dissonance they are likely to experience when confronted with information about animal exploitation. For many vegans, the moment they finally allowed themselves to face this dissonance honestly is precisely what triggered their transition to veganism.
Ultimately, carnist cognitive dissonance is not a personal failing but an inevitable by-product of an ideology built on contradictory moral expectations. Because the exploitation of nonhuman animals is embedded in culture, law, religion, economics, and family tradition, carnists are conditioned to reduce dissonance not by changing behaviour but by changing perception. Understanding this helps vegans recognise that the resistance they encounter in outreach is rarely about the argument itself — it is about the psychological discomfort that arises when someone’s values collide with their acquired carnist habits.
Cognitive Dissonance in Vegans
It is tempting for vegans — especially those who have experienced the profound clarity that comes with rejecting animal exploitation — to believe that we have “eliminated” our cognitive dissonance. After all, we changed our behaviour precisely because we could no longer justify actions that harmed other sentient beings. For many of us, becoming vegan felt like stepping out of a fog, but the truth is more nuanced: vegans have not lost their cognitive dissonance, but we have simply shifted it.
Many people who define themselves as vegans may only be imitating the behaviour of vegans rather than manifesting the philosophy of veganism, either because they are just plant-based people that eat what vegans eat, are new at veganism and they have not grasped the philosophy in all its dimensions yet, or are simply confused and they misinterpret what veganism is (despite there has been an official definition unchanged since 1988). These people may be having the same cognitive dissonance as carnists and experience the same contradictions between their beliefs and their actions. For instance, people who call themselves vegans but eat some animals (like oysters), consume eggs (like backyard eggs), eat honey or insects (or use products with beeswax), have exotic “pets” (like reptiles), visit zoos for leisure (including aquariums), or ride horses. Like the rest of carnists, these would have rationalised these inconsistencies, and like them, their cognitive dissonance would have made them avoid addressing them when challenged by true vegans. Also, people who call themselves vegan but who promote violence against others (like some aggressive misogynists), discriminate against other sentient beings (i.e. disregarding the welfare of wild animals or feeding companion dogs meat from cows), feel that humans are either superior (like some religious people) or inferior (like some misanthropes) to all nonhuman animals, or who think veganism is just a diet (like some health “influencers”), will also be the victims of cognitive dissonance as carnists are as their indoctrination remains strong.
However, in addition to these, we, ethical vegans who have been vegan for a while and try to follow the definition of veganism to the full avoiding violating any of its main principles (what I call the five main axioms of veganism), we still suffer from cognitive dissonance, but rather than experiencing it because of what we do, we often experience it because of what we continue to struggle with, tolerate, or witness in others.
One common source of dissonance for true vegans arises from the tension between the world we believe should exist — a world guided by ahimsa, justice, and respect for all sentient beings — and the world we still live in, where animal exploitation is everywhere. We oppose the use of fishes, birds, mammals, and other animals for food, entertainment, clothing, sport, science, or labour, but we simultaneously function within a society that normalises these practices, sometimes acting as if we accept them. We walk past shops selling animal flesh, we see leather shoes in public spaces, we hear conversations about barbecues, and we work in professions where exploitation is still the norm, but we are not constantly challenging all these things. The dissonance arises not from hypocrisy, but from the psychological stress of existing ethically within an unethical society.
Vegans may also experience dissonance when their behaviour does not perfectly match their ideals. No vegan is entirely free from indirect harm. We may purchase a vegan-friendly product from a non-vegan company, use public infrastructure funded by taxes from industries exploiting animals, or rely on medications that were tested on animals. If we did not have any practicable alternatives to these, this does not mean we are less vegan, but such choices can still provoke feelings of conflict because our guiding philosophy is rooted in trying to eliminate the harm we cause, not just reducing it. The discrepancy between the world we aspire to and the limited control we have over the real world we live in creates internal tension, which some vegans resolve with guilt, hyper-vigilance, or self-criticism. This is not moral weakness but the natural psychological outcome of caring deeply about others in a system designed to ignore them.
Another form of dissonance appears when vegans interact with non-vegans. We value respect, yet we may feel anger or frustration when confronted with carnist justifications or casual indifference to animal suffering. We value patience, yet we may lose it. We value open dialogue, yet we might avoid certain conversations to protect relationships. We value truth, yet sometimes we soften our message to avoid conflict.
There is also a more subtle dissonance that arises when vegans try to reconcile the enormity of global animal exploitation with the limitations of individual advocacy. We know the scale of harm. Trillions of fishes are killed each year, billions of land animals are raised and slaughtered, and countless wildlife are harmed by habitat loss, pollution, or pesticide use. Yet we must continue to live our lives, go to work, pay bills, and care for ourselves, and do it with a cheerful disposition to show others that becoming vegan does not prevent you from having a happy and fulfilled life. The ethical imperative of veganism urges us to do everything, but the human condition makes that impossible. This conflict between responsibility and capacity can create a unique kind of dissonance that only ethical vegans tend to experience.
Importantly, vegan cognitive dissonance is not something to be eradicated but something to be understood. It is a sign that our moral compass is functioning. Whereas the typical dissonance carnists experience shields them from recognising harm, the one that true vegans experience often highlights the areas where we want to grow, engage, or refine our activism. It can inspire us to deepen our understanding of intersectionality, refine our choices, expand our circle of concern, support more sanctuaries, challenge more habits and traditions, or develop more effective outreach strategies. In this sense, vegan cognitive dissonance can be a catalyst for moral evolution rather than a barrier to integrity.
Recognising our own dissonance also fosters respect for others. When we remember the mental journey that brought us to veganism, we are better equipped to understand the internal conflict that carnists may be experiencing — even when it manifests as anger, denial, or ridicule. This awareness allows us to approach outreach as a process of guiding others through their own psychological discomfort.
In the end, both carnists and vegans experience cognitive dissonance, but not always for the same reasons. Carnists experience it because their behaviour does not match their values, but true ethical vegans often experience it because their values do not yet match the world. Acknowledging this reality is one of the most powerful ways we can continue progressing toward a society where ahimsa is not the exception, but the norm.
Steps to Deal with Cognitive Dissonance Regarding Issues Involving Nonhuman Animals
Whether you are vegan or not, there are several steps we all can take to deal with cognitive dissonance in situations where nonhuman animals may be negatively affected by it. First, understand what cognitive dissonance is. Make sure we recognise it when we see it, and accept that, even if we think we got rid of it, we will still have it, as it is an intrinsic part of the human psyche.
Second, weaken its harmful influence. If we know that it is causing harm to others, we can address this by changing our behaviour to prevent such harm. If our behaviour clashes with our beliefs — creating a dissonance — changing the behaviour so it no longer clashes is an effective way to get rid of the dissonance — with all its psychological and emotional baggage. Often, changing the behaviour will be easier than you expected. So, for instance, if you are a pescatarian feeling bad about eating fishes as you know they suffer too, stop eating them, and that feeling will go away. If you are a vegan living with a companion dog, but you feel bad for feeding him the flesh of cows in the form of standard pet food, then stop doing it and feed him nutritionally complete plant-based “pet food” that already exists, and it has been proven to be healthy and appealing to dogs. In a way, veganism only exists because we have cognitive dissonance. We need a coherent, practical philosophy with specific “rules” to follow because, without it, our brains may gradually lead us to harm others by ignorance, complacency, intellectual laziness, or indoctrination. Once we know that, we can change our behaviour one at a time, so we experience fewer clashes between our values and actions.
Third, shift it away from carnism. In addition to having a brain built with cognitive dissonances (at least neurotypical brains, that is), we have grown up under a heavy indoctrination that exploits such dissonances not to help others but to oppress them. We might have been born with a brain we cannot change, but with the right effort and information, we can “deprogram” ourselves from the indoctrination of carnism. This is what veganism brings us. As a philosophy, it is an “antidote” against carnism. Not a complete cure, but a boost to our ideological “immune system” that will increase the chances we can neutralise such harmful indoctrination. Some philosophies and ideologies lead to more cognitive dissonance because they are not based on logic or common sense. Carnism is one of them, as it is based on violence, supremacy and dominion instead. Other philosophies lead to less dissonance because they are more cogent, coherent, and logical. Veganism is one of these, so if we replace your life-guiding philosophy from one more prone to dissonance to one less prone to it, you will experience fewer dissonances. Fully adopting the philosophy of veganism, not just changing our behaviour to make it vegan-friendly, will not only reduce the number of cognitive dissonances you will experience, but it will shift your natural cognitive dissonance from a malign outcome to a benign one.
Finally, address your remaining dissonance with honesty and humility. Once we have detected our dissonances, once we have changed our behaviour, once we have adopted veganism and actively resist carnism, we need to accept that some carnism may still linger in us, so we should never let our guard down, and every time we make a choice that affects other animals, we should think twice. We should ask ourselves, “Would I have chosen differently if that animal were a human?” or even better, “Would I have chosen differently if that animal were my daughter?” If the answer is “yes”, you may still have some cognitive dissonances that need addressing. The good news is that the more you do this, the easier it becomes to address them.
If you follow all these steps, you will be able to deal with cognitive dissonances in a productive way that will enrich you as a person and make you less harmful to the world.
Perhaps you never considered this before.
