Why We Like What We Like

Paul Bloom’s How Pleasure Works: The New Science of Why We Like What We Like provides a wonderful set of arguments for why we love what we love. In my own work I was struck that children seem to have automatic preferences toward social groups that mimic the adult state (in spite of far less experience) and have been working to understand these preferences and their origins. Paul’s book gave me several ideas that I hadn’t considered and I thought his proposals worth sharing more broadly. Enjoy!

Mahzarin R. Banaji

APS President

I am grateful to APS President Mahzarin Banaji for giving me the opportunity to discuss the science of pleasure.

One of the most exciting ideas in cognitive science is the theory that people have a default assumption that things, people, and events have invisible essences that make them what they are. Experimental psychologists have argued that essentialism underlies our understanding of the physical and social worlds, and developmental and cross-cultural psychologists have proposed that it is instinctive and universal. We are natural-born essentialists.

I propose that this essentialism not only influences our understanding of the world, it also shapes our experience, including our pleasures. What matters most is not the world as it appears to our senses. Rather, the enjoyment we get from something derives from what we think that thing really is. This is true for more intellectual pleasures, such as the appreciation of paintings and stories, but it is true as well for pleasures that seem more animalistic, such as the satisfaction of hunger and lust. For a painting, it matters who the artist was; for a story, it matters whether it is truth or fiction; for a steak, we care about what sort of animal it came from; for sex, we are strongly affected by who we think our sexual partner really is.

What motivates this sort of theory? After all, some questions about pleasure have easy answers, and these have little to do with essentialism. We know why humans get so much joy from eating and drinking. We know why we enjoy eating some things, such as sweet fruit, more than other things, like stones. We know why sex is often fun, and why it can be pleasing to look at a baby’s smiling face and listen to a baby’s laugh. The obvious answers are that animals like us need food and water to survive, need sex to reproduce, and need to attend to our children in order for them to survive. Pleasure is the carrot that drives us toward these reproductively useful activities. As George Romanes observed in 1884, “Pleasure and pain must have been evolved as the subjective accompaniment of processes which are respectively beneficial or injurious to the organism, and so evolved for the purpose or to the end that the organism should seek the one and shun the other.”

We still need to explain how it all worked out so nicely, why it so happens (to mangle the Rolling Stones lyric) that we can’t always get what we want — but we want what we need. This is where Darwin comes in. The theory of natural selection explains, without appeal to an intelligent designer, why our pleasures so nicely incline us toward activities that are beneficial to survival and reproduction — why pleasure is good for the genes.

This is an adaptationist theory of pleasure. It is quite successful for non-human animals. They like what evolutionary biology says that they should like, such as food, water, and sex. To a large extent, this is true of humans as well. But many human pleasures are more mysterious. I begin How Pleasure Works with some examples of this:

Some teenage girls enjoy cutting themselves with razors. Some men pay good money to be spanked by prostitutes. The average American spends over four hours a day watching television. The thought of sex with a virgin is intensely arousing to many men. Abstract art can sell for millions of dollars. Young children enjoy playing with imaginary friends and can be comforted by security blankets. People slow their cars to look at gory accidents and go to movies that make them cry.

Consider also the pleasures of music, sentimental objects (like a child’s security blanket), and religious ritual. Now, one shouldn’t be too quick to abandon adaptationist explanations, and there are some serious proposals about the selective advantages of certain puzzling pleasures: The universal love of stories might evolve as a form of mental practice to build up vicarious experience with the world, and  to safely explore alternative realities. Art and sports might exist as displays of fitness. Animals constantly assess one another as allies and mates; these human activities might be our equivalent of the peacock’s tail, evolved to show off our better selves. Music and dance might have evolved as a coordinating mechanism to enhance social cooperation and good feelings toward one another.

Still, this approach is limited. Many of our special pleasures are useless or maladaptive, both in our current environment and the environment in which our species has evolved. There is no reproductive benefit in enjoying security blankets, paintings by Kandinsky, or sexual masochism.

Many psychologists are wary of adaptationist explanations and would defend the alternative that our uniquely human pleasures are cultural inventions. They don’t doubt that human brains have evolved, but they argue that what humans have come to possess is an enhanced capacity for flexibility; we can acquire ideas, practices, and tastes that are arbitrary from a biological perspective.

This plasticity theory has to be right to some extent. Nobody could deny that culture can shape and structure human pleasure; even those pleasures that we share with other animals, such as food and sex, manifest themselves in different ways across societies. Taken to an extreme, then, one might conclude that although natural selection played some limited role in shaping what we like — we have evolved hunger and thirst, a sex drive, curiosity, some social instincts — it had little to do with the specifics. In the words of the critic Louis Menand, “every aspect of life has a biological foundation in exactly the same sense, which is that unless it was biologically possible, it wouldn’t exist. After that, it’s up for grabs.”

I spend much of How Pleasure Works arguing that this is mistaken. Most pleasures have early developmental origins  — they are not acquired through immersion into a society. And they are shared by all humans; the variety that one sees can be understood as variation on a universal theme. Painting is a cultural invention, but the love of art is not. Societies have different stories, but all stories share certain themes. Tastes in food and sex differ — but not by all that much. It is true that we can imagine cultures in which pleasure is very different, where people rub food in feces to improve its taste and have no interest in salt or sugar, or where they spend fortunes on forgeries and throw originals into the trash, or spend happy hours listening to static, cringing at the sound of a melody. But this is science fiction, not reality.

I think that humans start off with a fixed list of pleasures and we can’t add to that list. This might sound like an insanely strong claim, given the inventions of chocolate, video games, cocaine, dildos, saunas, crossword puzzles, reality television, novels, and so on. But I would suggest that these are enjoyable because they connect — in a reasonably direct way — to pleasures that humans already possess. Hot fudge sundaes and barbecued ribs are modern inventions, but they appeal to our prior love of sugar and fat. There are novel forms of music created all the time, but a creature that was biologically unprepared for rhythm would never grow to like any of them; they will always be noise.

Some pleasures, then, are neither biological adaptations nor arbitrary cultural inventions. This brings us to a third approach, explored in my book, which is that many of our most interesting pleasures are evolutionary accidents.

The most obvious cases here are those in which something has evolved for function X but later comes to be used for function Y — what Darwin called “preadaptations.” As a simple example, many people enjoy pornography but this isn’t because our porn-loving ancestors had more offspring than the porn-abstainers. Rather, certain images have their effect, at least in part, because they tickle the same part of the mind that responds to actual sex. This arousal is neither an adaptation nor an arbitrary learned response —  it’s a byproduct, an accident. I have argued elsewhere that the same holds for the human capacity for word learning. Children are remarkable at learning words, but they do so, not through a capacity specifically evolved for that purpose, but through systems that have evolved for other functions, such as monitoring the intentions of others. Word learning is a lucky accident.

More specifically, many of our pleasures may be accidental byproducts of our essentialism. Different sorts of essentialism have been proposed by psychologists. There is category essentialism, which is the belief that members of a given category share a deep hidden nature. This includes belief in the physical essences of natural things like animals and plants, where the essence is internal to the object, as well as belief in the psychological essences of human-made things such as tools and artwork, where the essence is the object’s history, including the intentions of the person who created it. Then there is individual essentialism, which is the belief that a given individual has an essence that distinguishes it from other members of its category, even from perfect duplicates.

Our essentialist psychology shapes our pleasure. Sometimes the relevant essence is category essence, such as in the domain of sex, where the assumed essences of categories such as male and female turn out to powerfully constrain what people like. Sometimes the relevant essence is individual essence, which helps capture how certain consumer products get their value — such as an original painting by Marc Chagall or John F. Kennedy’s tape measure (which sold for about $50,000). More generally, the proposal is that our likes and dislikes are powerfully influences by our beliefs about the essences of things.

I hope my book sparks debate over these different theories of why we like what we like. In a recent discussion, Paul Rozin has worried about the narrowness of the modern sciences of the mind and points out that if you look through a psychology textbook you will find little or nothing about sports, art, music, drama, literature, play, and religion. These are wonderful and important domains of human life, and we won’t fully understand any of them until we understand pleasure.