Sex, Drugs and Chocolate: The Science of Pleasure

Augustus was succeeded by Tiberius, who succumbed to what Suetonius calls ‘all the vicious passions’. In his youth, Tiberius Claudius Nero was such a heavy drinker that he acquired the nickname ‘Biberius Caldius Mero’, meaning ‘drinker of hot undiluted wine’. (There will be no more Latin jokes in this book, I promise.) As emperor, he demonstrated the double standards of many rulers up to the present day: while campaigning publicly to raise standards of morality, he spent much of his private time in orgies of feasting, whoring and boozing. Hedonism even acquired a bureaucratic status under Tiberius, who established the official position of Comptroller of Pleasures.

Tiberius’s hedonism burgeoned after he retired to his private pleasure-ground of Capri. There, Suetonius tells us, groups of young men and women performed exotic sexual acts in front of the emperor to titillate his ageing libido. The rooms of his Capri pleasure palace were decorated with the most erotic pictures, books and statues obtainable, including sex manuals from Egypt and puppets demonstrating ‘wanton postures’. Suetonius found certain aspects of Tiberius’s lewdness too vile to elaborate on, although he drops some pretty strong hints. Young boys, whom Tiberius called his little fishes, were trained to follow him when he went swimming and to get between his legs and lick and nibble him. We are also told that Tiberius used babies not yet weaned from their mother’s breast ‘to suck at his breast or groin’. On one occasion, the disgusting old lecher took a fancy to a young acolyte at a ceremonial sacrifice; he could barely wait for the ceremony to end before bundling the young man and his brother, who was the sacred trumpeter, out of the temple and indecently assaulting both of them. When they protested at his outrageous behaviour he had their legs broken. Tiberius was succeeded by Gaius, known as Caligula, who continued in much the same way.

Caligula pursued every imaginable form of pleasure with energetic abandon. One of his favourite pastimes was to watch people being tortured and executed. According to Suetonius, he had no regard for anyone’s chastity and enjoyed large numbers of homosexual relationships. One young man revealed publicly that he had ‘buggered the emperor’ and quite worn himself out in the process. Caligula had sex with most women of rank in Rome, including his three sisters. After inviting a selection of respectable ladies to dinner with their husbands, he would examine each one in turn. Later, when the mood took him, he would summon his choice and leave the banquet to have sex with her. After returning to the meal, he would openly discuss her performance with his guests. Caligula’s many other indulgences included drinking pearls dissolved in vinegar and feeding golden bread to his dinner guests. Unsurprisingly, it took him less than a year to squander his fortune. Caligula died at the age of twenty-nine and was succeeded by Claudius.

Claudius continued the imperial tradition of drunkenness, gambling, womanising and feasting. After developing a burning passion for his niece, he changed the law so that he could marry her. Claudius was a renowned trencherman who rarely left a dining-hall until he was ‘gorged and sodden’, whereupon a servant would put a feather down his throat to make him vomit so that he could start gorging again. He was also a devoted gambler and published a book on the subject. Claudius was succeeded by Nero – a name that has done more than most to give hedonism its dark reputation.

Nero’s pleasure-seeking knew no boundaries, leading one modern commentator to describe him as one of the biggest creeps in history. His feasts lasted from midday to midnight and his guests would generally include a substantial contingent of prostitutes. Like his predecessors, Nero enjoyed plentiful sex with men and women. He had one of his favourite slaves castrated and then married him. His more mundane excesses included never wearing the same clothes twice and using a golden net for fishing. Another in a long line of imperial gamblers, he would often stake thousands of gold pieces on a single throw of the dice.

Nero was succeeded briefly by Galba, whose two main characteristics, according to Suetonius, were cruelty and greed. He was a heavy eater and a homosexual with a penchant for ‘mature and very sturdy men’. Galba died after less than seven months as emperor, to be succeeded by Otho, whose reign was even briefer. Next in line came Vitellius, who had spent his adolescence among Tiberius’s male prostitutes on Capri. As emperor, Vitellius became notorious for every sort of self-indulgence. He banqueted three or four times a day, often making himself vomit to create space for more. For one feast, he commissioned a dish containing ingredients from every corner of the empire, including pike livers, peacock brains, flamingo tongues and lamprey milt. Suetonius describes Vitellius as unusually tall, with an alcoholic flush, a huge paunch and a crippled thigh. He was succeeded by Vespasian, who was a model of virtue by comparison. Vespasian liked to nap, which makes him a big favourite of mine. (We will return to the joys of napping in the final chapter.) His successor was Titus.

Suetonius describes Titus as profligate and cruel. He held riotous parties far into the night and owned a troupe of homosexual prostitutes and eunuchs. Titus was succeeded by Domitian, whose lustfulness was of a high order, even by the standards of the day. Domitian referred to sex as ‘bed-wrestling’ and treated it like a competitive sport. He enjoyed swimming with prostitutes, shaving his concubines’ pubic hair and having sex with married women.

The behaviour of the Caesars and subsequent emperors did little to improve the tawdry image of hedonism. Nonetheless, hedonism has had its principled defenders. One of its most vociferous advocates was the Greek philosopher Aristippus, who died in 366 BC. He contended that pleasure (hedone) could be equated with good and that every person should live their life so as to maximise pleasurable experiences.

(#litres_trial_promo) Aristippus vigorously practised what he preached, acquiring a reputation as a man who really knew how to have a good time. When he was not mounting a defence of hedonism he could usually be found mounting someone else.

Around the same period as Aristippus, the Chinese philosopher Yang Chu was also championing the idea that we have only one life and should enjoy it as much as we can. Yang Chu espoused a simple – some would say simplistic – philosophy of hedonism. Life is short, he argued, and the only truly good things in it are the sensual pleasures of music, sex, fine clothes and tasty food. His ideas were later absorbed into the Taoist philosophical tradition. Several hundred years after he died, his ideas resurfaced in the Taoist Book of Lieh-tzu. In one passage, Yang Chu’s starkly hedonistic worldview is expressed in an argument that goes like this. The longest any of us can hope to live is a hundred years. Even if we are lucky enough to live that long, half our useful life is lost in unconscious infancy and old age. Of the remaining years, a further half is either wasted or spent asleep. Pain, sickness, sorrow and fear use up at least half the rest. That leaves us only about ten years for enjoyment. Even then, every hour is plagued with anxiety because we are driven by social pressures to conform and achieve. Our anxieties prevent us from enjoying ourselves, leaving us no better off than chained criminals. Instead, we should spend our time seeking pleasure from sex, good living, beauty and music. Yang Chu was exhorting us in clear and simple terms to grab pleasure while we can – or, as others have variously put it, to eat, drink and be merry, seize the day, and gather rosebuds while ye may.

In the post-Enlightenment England of the eighteenth century, there was much gathering of rosebuds, reflecting a widespread view that humans were built to pursue pleasure and that doing so was good for society as a whole. Growing affluence made this aspiration a reality for many. The pleasure industry boomed – not just for the enjoyment of the rich and powerful, but for the masses. Whole towns became devoted to enjoyment. The Prince Regent chose Brighton as the site for his pleasure palace and millions of fun-seekers followed him there. Resorts such as Bath, Cheltenham and Buxton made their wealth from visitors seeking health and pleasure. Predictably, the quest for pleasure often trumped the quest for health, prompting much sniping from moralisers. The Methodist preacher Charles Wesley described Bath as ‘Hell on earth’.

Georgian London was known for its two hundred or so pleasure gardens. Among the most famous was Vauxhall Gardens, which was renowned for its erotic ambience. Men and women of all backgrounds could stroll, dance, eat, drink and enjoy themselves to the sound of music. Anyone who could afford the modest entrance fee had the prospect of an erotic encounter. Ranelagh in Chelsea was said to be favoured by the greatest beauties and was described by one contemporary writer as the finest market in England.

Sexual activity was widely regarded at this time as a legitimate source of pleasure rather than a sin. Erasmus Darwin, grandfather of Charles Darwin and an eminent scholar himself, described sex as ‘the purest felicity in the otherwise vapid cup of life’. Sex was easily obtained on a commercial basis. As many as 30,000 streetwalkers plied their wares in the streets of Georgian London. Any punter interested in ‘country matters’ could buy publications such as Harris’sList of Covent Garden Ladies or The Man of Pleasure’s Kalendar, which listed the local prostitutes and detailed their erotic specialities. James Boswell wrote in his diary that it was impossible to stroll in St James’s Park or walk down the Strand without being propositioned by scores of harlots – something he found hard to resist.

A prominent figure of this period was Teresa Cornelys, otherwise known as the Empress of Pleasure. She created London’s first exclusive nightclub. The Society in Soho-Square, as it was called, was based in her Soho mansion and opened for business in 1760. It was a glittering pleasure palace for the rich, which helped establish Soho’s abiding association with hedonism. A typical night there would start with a concert performed by top musicians in sumptuous surroundings. Then the real fun would begin, as the guests ate, drank, danced and gambled until dawn, some slipping away to discreet bedrooms for more intimate pleasures. The English were as obsessed with celebrities then as they are now: crowds of onlookers would swarm around Soho Square, hoping to catch a glimpse of the rich and famous, including younger members of the royal family.

All this bawdy revelry upset the Church, which tried hard to have The Society in Soho-Square shut down. In 1770 the bishop of London begged the king to ban a huge masked ball that Cornelys was arranging, but his pleas fell on deaf ears. Salt was later rubbed in the ecclesiastical wound when it transpired that the guests included the bishop’s own wife and the wives of three other senior clerics. Religious and secular attempts to constrain pleasure-seeking is an eternal theme that we shall return to later.

Teresa Cornelys’s genius at creating pleasure for others was a natural reflection of her background. She came originally from Venice, a city where the pursuit of pleasure had become an art form. She travelled to London with her child, whose father was none other than Giacomo Casanova. Teresa Cornelys was born close to Casanova’s family home in Venice and they met in their teens. Their mutual love of pleasure made them kindred spirits.

Casanova managed to pack more sensual experience into his life than most of us could dream of. Born in 1725, he died seventy-three years later, having variously been a novelist, poet, gambler, soldier, musician, spy, adventurer, free-thinker and prolific lover. He travelled widely, forged relationships with many famous people and enjoyed everything that life had to offer. When Casanova came to write his memoirs, shortly before his death, he looked back with evident enjoyment. ‘What pleasure’, he wrote, ‘in remembering one’s pleasures!’ He felt little regret at how he had chosen to live his life:

Cultivating the pleasures of the senses was my principal concern throughout my life; none, indeed, was ever more important to me. Feeling as though I was born for the fair sex, I have always loved it and let it love me as much as I could. I have also passionately loved good food and all things made to arouse curiosity.… As a great libertine, a bold talker, a man who thought only of pleasure in life, I could not find myself guilty of anything.

Back in Georgian England, the pleasure-seekers were receiving heavyweight support from a number of prominent thinkers. Foremost among these was the philosopher Jeremy Bentham. Like Aristippus before him, Bentham regarded pleasure as the ultimate aim in life. He famously argued that behaviour, morals and laws should be judged according to how much they fostered ‘the greatest happiness of the greatest number’. As far as Bentham and like-minded Utilitarians were concerned, humans were intended by nature to seek pleasure and avoid pain. In 1785 he wrote an essay entitled ‘Paederasty’, in which he argued that society’s disapproval of anal sex stemmed from an irrational antipathy towards pleasure, especially sexual pleasure. Bentham even tried to devise an objective method for calculating exactly how much ‘felicity’ any particular action would unleash, but this proved too difficult. Indeed, it remains the case to this very day that no one is entirely sure how best to quantify happiness or pleasure.

Strong echoes of Bentham’s philosophy are evident in current thinking that national governments should pursue policies and enact laws that are specifically intended to maximise national happiness, in contrast with their conventional preoccupation with maximising national wealth. However, it is often unclear what the proponents of such policies really mean by ‘happiness’, which they sometimes seem to equate with pleasure, or just feeling good. As we shall see later, pleasure and happiness are two quite different entities.

What does hedonism look like in the early twenty-first century? Much the same as in Georgian London or imperial Rome, it would appear. A far wider variety of mind-altering drugs is now available, but the familiar mainstays of sex, alcohol, food and gambling remain as popular as ever. In the UK, for example, the average household devotes about 4 per cent of its total expenditure to those two ancient and deeply entrenched drugs, alcohol and tobacco. Psychological research and social surveys consistently find that people around the world continue to derive most of their pleasure from having sex, eating, drinking, relaxing and socialising with family and friends. In private, many of them also seek chemical pleasure from illicit drugs, which is why drug trafficking is estimated to account for around 8 per cent of all international trade. But enough of the social history: it is time now for a little science.

TWO What Is Pleasure For? (#ulink_104e5da9-f826-503d-a8d0-9150c0dfb2f2)

Pleasure is the only thing worth having a theory about.

OSCAR WILDE,

The Picture of Dorian Gray (1891)

What is pleasure for? That is the sort of question biologists ask. What they mean is: how did this feature of our biological makeup help our ancestors to survive and reproduce, and therefore to become our ancestors? To put it another way, why did evolution equip us and other animals with the capacity and appetite to experience pleasure in so many varied and delightful ways, including perhaps some that are still undiscovered?

The simplest answer is that pleasure and its dark counterpart, pain, are there to encourage us to do the right things. Pleasure entices us to behave in ways that are likely to be biologically beneficial, while pain discourages us from doing ourselves harm. The ever-shifting balance between pleasure and pain is, to quote the philosopher David Hume, ‘the chief spring or actuating principle of the human mind’.

The idea that pleasure and pain direct our behaviour has been circulating in various guises for thousands of years, dating back at least as far as Epicurus and like-minded philosophers of ancient Greece. Psychology, as it came to be known, built upon this simple concept in the nineteenth century. In 1880, for example, Herbert Spencer advanced a specific psychological theory that all human behaviour is underpinned by the twin motivating forces of pleasure and pain.

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Sigmund Freud pursued the theme with his psychoanalytic Pleasure Principle. In his characteristically doubt-free style, Freud asserted that he had no hesitation in assuming that all mental activity was ‘automatically regulated’ by the Pleasure Principle – by which he meant that all mental activity was directed towards the production of pleasure or the avoidance of displeasure. Freud decided that pleasure and displeasure were reflections of a mental phenomenon that he called ‘unbound excitation’; pleasure supposedly acted to reduce this excitation, while displeasure did the reverse. In another of his works, an even less hesitant Freud proclaimed that ‘It is simply the programme of the pleasure principle that determines the purpose of life.’

What has science, as distinct from Freudian conjecture, revealed about pleasure? One basic conclusion is that the behaviour of humans and other animals is self-evidently motivated by stimuli that are associated with pleasure. Pleasurable rewards (or ‘reinforcers’) tend to increase the frequency of the behaviour that produced them, whereas unpleasant stimuli do the reverse. The long-suffering experimental pigeon will peck energetically at a button if its efforts are rewarded with food, but it will rapidly stop pecking and avoid the button if instead it receives a mild electric shock.

A second basic conclusion is that the sorts of activities we find pleasurable could mostly be viewed as biologically beneficial, in the sense that they would generally have helped our ancestors to survive and reproduce in their natural environment. As we saw earlier, people consistently report that socialising, having sex and eating are their main sources of pleasure. These activities are also biologically beneficial, in the right circumstances. Even the simplest pleasures of life, like warming yourself in front of a fire or tending a garden, make good biological sense if you imagine yourself as one of your hunter – gatherer ancestors.

The capacity to respond to pleasurable stimuli emerged very early in evolution and is detectable, in one form or another, in animals ranging from flies and shellfish to dogs and gorillas. Pleasure almost certainly plays a bigger role in the lives of other species than we humans often tend to assume. The neuroscientist Jaak Panksepp has even uncovered evidence that rats are capable of experiencing playful joy which they express in the form of high-pitched ‘laughing’. When a rat has a joyful experience, such as playing with another rat, it emits a series of ultrasonic (50-kilohertz) chirps. Panksepp contends that these vocalisations are biologically related to the joyful laughter that children emit when they are playing. The thought that rats enjoy a giggle with their mates is a reminder that life for other species can amount to more than just a grim struggle for survival.

If pleasure did evolve to guide our behaviour, then how does it perform this biological function? The task is not quite as straightforward as it might seem. At any given moment we could be doing many different but mutually exclusive things, each of which would be biologically beneficial. We might, for example, be faced with the choice of cooking dinner, sleeping in a cosy bed or having vigorous sex. How do we decide what to do next? Humans and other animals must continually choose between competing requirements. We therefore require some form of mechanism for weighing the conflicting motivations against each other and choosing the best option at the time. To help us choose, we need some form of measuring stick or common currency. According to the physiologist Michel Cabanac, that common currency is pleasure.

The essence of Cabanac’s theory is that pleasure enables the brain to compare the strengths of current motivations to perform different activities. When choosing between, say, eating, staying warm or avoiding danger, we may, of course, make a conscious, rational judgement about our priorities. But even an apparently conscious decision will be influenced by an unconscious weighing of the options in terms of how much pleasure or displeasure each would produce. We are drawn towards the most pleasant, or least unpleasant, course of action. This simple form of hedonism encourages us to behave in ways that, on average, will be in our best biological interest.

Pleasure is the hidden force behind what might be called ‘gut instinct’; it guides our choices even when we think we are using our conscious mind to make rational decisions. Experimental tests have lent support to this simple theory, confirming that humans and other animals behave in line with its detailed predictions. We make unconscious but surprisingly precise trade-offs between the amount of displeasure we are prepared to experience and the amount of pleasure we anticipate in return. The evidence suggests that something akin to pleasure is used to prioritise actions in other species as well. Even a lizard will be guided by the unconscious trade-off between, say, physical discomfort and the attractiveness of food.

If evolution has equipped us with pleasure as a mechanism to help guide our behaviour then we would expect those feelings of pleasure to be inherently transient and self-limiting. Faced with competing priorities, we will choose the most pleasant or the least unpleasant course of action. But in order to survive and thrive, we must stop performing that activity and switch to something else as soon as our current needs have been satisfied and other priorities have risen to the fore. If a pleasurable activity continued to be pleasurable for too long, we would be in danger of getting locked into doing it and therefore neglecting higher-priority needs. Our ancestors would not have survived long enough to become our ancestors if they had sunk into a state of enduring bliss every time they did something enjoyable. For pleasure to do its biological job as a motivational common currency, it must be short-lived. And so it is.

Everyday experience, backed up by a reassuring mass of experimental data, confirms that pleasure is indeed short-lived. We habituate quite rapidly to pleasurable sensations. No matter how earth-shaking it may be at the time, any given pleasure will fade and the moment will pass. William Shakespeare famously encapsulated this aspect of human nature in the opening lines of Twelfth Night:

If music be the food of love, play on;

Give me excess of it, that, surfeiting,

The appetite may sicken, and so die.

The ephemeral nature of pleasure has important practical implications, which we will explore later. Above all, it means that anyone who attempts to rely exclusively on pleasure to make them happy is likely to have a struggle on their hands. The present pleasures will inevitably dwindle, forcing the determined hedonist to keep increasing the dosage or switch to new ones. Socrates likened pleasure-seekers to the damned in Hell, who are condemned for ever to keep trying to fill leaky jars. Psychologists refer to this phenomenon as the hedonic treadmill.

Pleasure must be self-limiting to do its job. However, biological reasoning would suggest that displeasure and pain should not be self-limiting in the same way. Instead, they should persist for as long as the problem that gives rise to them. If the biological function of displeasure and pain is to protect us from harm, we would expect them to linger until the corresponding threat to our well-being has gone away. Again, the theory is borne out by reality. Unpleasant feelings such as anxiety, fear and pain are generally not as ephemeral as pleasure; we do eventually adjust to displeasure or pain, but more slowly and less completely than in the case of pleasure. As the essayist William Hazlitt put it, ‘pain is a bittersweet, which never surfeits’.

The simple idea that pleasure evolved to make us behave in biologically beneficial ways further implies that there should be a clear relationship between our current biological needs and our current experience of pleasure. As those needs change, so too should our response to pleasurable stimuli. Once again, the theory is in line with everyday reality and experimental evidence. Our response to potentially pleasurable stimuli does indeed vary according to our current internal state and needs. Drinking tepid, murky water from a chipped mug can be delightful when you have a raging thirst, but not otherwise. Similarly, sinking into a steaming hot bath is altogether more pleasant when you are cold and wet than it is after a day of sunbathing on a tropical beach. Experimental studies have confirmed that changes in our internal state affect the amount of pleasure or displeasure we experience in response to stimuli. In one typical experiment, hungry people were repeatedly given drinks of sugary water, which they had to spit out without swallowing. They continued to find the sweet taste pleasant each time they experienced it. But if, instead, they swallowed each drink when it arrived, the sweet taste became progressively more unpleasant. Sweet pleasure turned to cloying displeasure as their stomach filled with sugary liquid. The same physical stimulus could elicit pleasure or displeasure, depending on the individual’s current internal state.

The idea that pleasure and other emotions are reflections of our body’s physical state has a long pedigree. William James, the pioneering nineteenth-century psychologist (and brother of writer Henry), proposed that our emotions arise, at least in part, from an awareness of our physical reactions to stimuli.

(#litres_trial_promo) So, for example, we feel afraid because we have become aware that our heart is pounding and our hands are trembling, rather than the other way round. James realised that if emotions are linked to internal state then we might be able to alter our emotions by manipulating the signals reaching the brain from the rest of the body. He tested this hypothesis with a very simple experiment. He smiled. More specifically, he forced his facial muscles to form the shape of a smile, even though he did not feel in the mood for smiling. (William James suffered from depression – hence, perhaps, his particular attraction to smiling.) He found that the more he smiled, the jollier he felt. The physical act of smiling was enough to elicit the corresponding emotional state, as though the configuration of his facial muscles had somehow tricked his brain into believing that he must be feeling good.

The two-way relationship between facial expression and emotion has been substantiated by more systematic experiments. In one study, psychologists got people to hold a pencil between their teeth without it touching their lips. This made them smile, without being consciously aware of doing so. As William James would have predicted, the physical act of smiling lifted their subjective mood, even though the subjects did not know they were smiling. By comparison, sucking a pencil with their lips wrapped around it did nothing to lift their mood. Similar mood-enhancing effects have been produced by giving experimental volunteers detailed instructions to move particular muscles in their face, causing them unwittingly to smile. The effect is strongest when the smile is of the so-called Duchenne variety – the ‘genuine’ type of smile that involves the corners of the eyes as well as the mouth. One day, perhaps, the well-read pleasure-seekers among us will be recognisable from the tell-tale pencil clenched between their teeth.

Deliberately smiling really can lift your mood. Try it for yourself. Use a pencil if you must. So too can holding your head high or whistling a happy tune. In each case, a physical act that would normally reflect an underlying emotional state can also elicit that same emotional state. Of course, people who never stop smiling can irritate those of us in a less ebullient mood, especially if their smile is obviously fake. Some celebrities develop a permanent rictus, which can vary from self-satisfied to borderline psychopathic. Nonetheless, they are on to something. Even a fake smile can make us feel a bit better, because the feedback from the facial muscles tells the brain that something good must be happening. The feel-good factor is reinforced if the smile evokes friendly responses from other people. The idea that emotions reflect some sort of mental map of the body’s internal state is further supported by brain-scanning studies, which show that pleasure and other emotions are accompanied by activity in parts of the brain that are known to be involved in monitoring the body’s internal state.

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At first sight, then, it might appear as though we have cracked the scientific puzzle of pleasure at an awkwardly early stage in this book. According to the simple theory just outlined, activities that are generally good for us are pleasurable and that is why we keep doing them. Pleasure is the brain’s universal currency, which it uses to compare different behavioural options. We plump for the activity that is likely to produce the most pleasure or the least displeasure, having unconsciously taken account of our current biological needs. If this explanation seems too simple, that is because it is too simple.