Emotions are as messy as they are fascinating, not just personally but scientifically, too. Although we are sure we know them when we feel them, it’s hard to even say what counts as an emotion. Anger, sadness and disgust, sure. But determination? Lust? Awe?
As Leonard Mlodinow shows in his new book, emotions are evolutionarily ancient, rooted in genes and brain structures we share with insects. And at the same time they are embedded in complex and sophisticated cultural scripts and schemas. Fago is a term the Ifaluk of Micronesia use to describe a mix of love, sadness, pity and an urge to feed someone. And how about ambivalence or schadenfreude?
Key to Mlodinow’s understanding of emotions are our basic bodily sensations, what he calls “core affect”, as anyone who has diagnosed a “hangry” spouse will recognise. Parole officers are more likely to deny parole as they get nearer to lunchtime, and gut instincts really do seem to be connected to your gut. But both classic and more recent studies show that people interpret these sensations in different ways. In one experiment, one group got a shot of adrenaline that made them vaguely aroused, and another got a placebo. Then everyone sat next to a confederate who acted either happy or angry. The placebo group didn’t report any emotion, but the other group reported happiness or anger depending on their social context.
Emotions play an important part in provoking actions. If cool reason allows us to appraise what will happen if we do something, it often takes hot emotion to get us to actually do it. As Mlodinow describes, emotions also often seem to act as a kind of quick summary of complex unconscious calculations about what to do. In artificial intelligence they talk about the frame problem: like Hamlet, an AI can get caught in an endless loop of rumination about what to do – and the philosopher Ronald de Sousa has suggested that emotions are evolution’s way of solving that problem. But at the same time emotions, particularly in humans, are social signals. Crying when you’re sad doesn’t make you feel better – it may even make you feel worse. But it does make other people want to protect and care for you.
Yet another undeniable feature of emotions is that you are conscious of them, and indeed feel them more vividly than other mental states such as thoughts, or beliefs or even goals and desires. Many approaches to consciousness focus on sophisticated cognitive states like a sense of the self, or the ability to manipulate thoughts in working memory. But recent work in evolutionary biology, nicely encapsulated in Peter Godfrey-Smith’s book Metazoa, argues that consciousness may have arisen first in the Cambrian explosion. Suddenly creatures developed new ways of perceiving prey or predators, such as eyes and feelers, and new ways of acting on them, such as pincers and claws and legs. The foundational sentient feelings that go with those simple actions, pain or hunger, this is good, this is bad, seem much closer to emotions than to thoughts.
Mlodinow chronicles many of the disparate neural, evolutionary, social, cultural, cognitive and phenomenological aspects of emotion within what has become something like the received form for popular science books – the equivalent of the sonnet rhyme scheme. Instead of A, B, C and D, Mlodinow alternates between study summaries, illustrative stories and self-help tips. The studies are mostly interesting and clearly described, and the stories, especially those about his Holocaust survivor parents, are well told and moving. The advice, as it generally does, boils down to: exercise, meditate, stay away from junk food and, as Sydney Smith wrote in 1820 in a letter of advice that is still the best self-help listicle ever: “Make no secret of low spirits to your friends, but talk of them freely – they are always worse for dignified concealment.” (Smith’s “Take short views of human life – not further than dinner or tea” is even more helpful.)
What’s missing from the book, and the standard popular science form in general, are theories and explanations – the heart of science. This may reflect the subject matter as much as Mlodinow’s telling of it. There is often an inverse relationship between how much psychological phenomena lend themselves to stories – how compelling they are – and how much they lend themselves to scientific explanations. There are elegant theories of visual perception and fine motor control that combine experiments, computations, neuroscience and evolutionary theory but, unlike emotions, vision and motor control don’t lend themselves to personal stories or propulsive narratives and – not to put too fine a point on it – they can be kind of boring. I think most writers trying to convey science to a broad audience struggle with this tension between the enviable properties of narrative – the way a good story naturally captures and guides a reader’s attention, and the fact that narrative just isn’t the right medium for scientific theories.
Although Mlodinow introduces the book by saying that there has been a revolution in our understanding of emotion, what emerges is not a clear new theory so much as a set of disparate bits and pieces, studies and stories collected over the past few years. His main theoretical point is that emotions are important and adaptive, not simply distractions and stumbling blocks to reason. That’s not a terribly new idea or one that depends on scientific studies – David Hume famously said reason is and ought only to be the slave of the passions, and even Plato thought the horses of reason and passion had to be ridden in tandem. But it is surely true.