I thought I understood cultural evolution. But in his new book, The Secret Of Our Success: How Culture Is Driving Human Evolution, Domesticating Our Species, and Making Us Smarter, Joseph Henrich schooled me. I felt like I learned more from his book than from the last dozen books I’ve read. For example, on the cultural plasticity of pleasure and pain:

Chili peppers were the primary spice of New World cuisines prior to the arrival of Europeans and are now routinely consumed by about a quarter of all adults globally. Chili peppers have evolved chemical defenses, based on capsaicin, that make them aversive to mammals and rodents but desirable to birds. In mammals, capsicum directly activates a pain channel (TrpV1), which creates a burning sensation in response to various specific stimuli, including aside, high temperatures, and allyl isothiocyanate (which is found in mustard and wasabi). These chemical weapons aid chili pepper plants .. because birds provide a better dispersal system for the plants’ seeds. .. People come to enjoy the experience of eating chili peppers mostly by reinterpreting the pain signals caused by capsicum as pleasure or excitement. .. Children acquire this preference gradually, without being pressured or compelled. They want to learn to like chili peppers, to be like those they admire. .. Culture can overpower our innate mammalian aversions when necessary and without us knowing it. ..

Runners like me enjoy running, but normal people think running is painful and something to be avoided. Similarly weight lifters love that muscle soreness they get after a good workout. .. Experimental work shows that believing a pain-inducing treatment “helps” one’s muscles activates our opioid and/or our cannabinoid systems, which suppress the pain and increase out pain tolerance. ..

Those who saw the tough model [who reported lower pain ratings] showed (1) .. bodies stopped reacting to the threat, (2) lower and more stable heart rates, and (3) lower stress ratings. Cultural learning from the tough model changed their physiological reactions to electric shocks.

Henrich’s basic story is that from a very early age we look to see who around us who other people are looking at, and we they try to copy everything about those high prestige folks, including their values and preferences. In his words:

Humans are adaptive cultural learners who acquire ideas, beliefs, values, social norms, motivations, and worldview from others in their communities. To focus our cultural learning, we use cues of prestige, success, sex, dialect, and ethnicity, among others, and especially attend to particular domains, such as those involving food, sex, danger, and norm violations. .. Humans are status seekers and aware strongly influence by prestige. But what’s highly flexible is which behaviors or actions lead to high prestige. …The social norms we acquire often come with internalized motivations and ways of viewing the world (guiding our attention and memory), as well as with standards for judging and punishing others. People’s preferences and motivations are not fixed.

The examples above show cultural influence can greatly change the intensity of pain and pleasure, and even flip pain into pleasure, and vice versa. Though the book doesn’t mention it, we see similar effects regarding sex – some people come to see pain as pleasure, and others see pleasure as pain.

All of this suggests that human preferences are surprisingly plastic. Not completely plastic mind you, but still, we have a big capacity to change what we see as pleasure or pain, as desirable or undesirable. Yes we usually can’t just individually will ourselves to love what we hated a few hours ago. But the net effect of all our experience over a lifetime is huge.

It seems that this should make us worry less that future folks will be happy. Even if it seems that future folks will have to do or experience things that we today would find unpleasant, future culture could change people so that they find these new things pleasant instead. Yes, if change happens very fast it might take culture time to adapt, and there could be a lot of unhappy people during the transition. And yes there are probably limits beyond which culture can’t make us like things. But within a wide range of actions and experiences, future folks can learn to like whatever it is that their world requires.