There is no doubt that what everybody wants is happiness. The only problem is what being happy consists in, an issue that moral thinkers have never been able to agree on and probably never will. Is happiness a purely subjective feeling, or can it be somehow measured? Can you be happy without knowing it? Can you only be happy without knowing it? Could someone be thoroughly miserable yet be convinced they were in ecstasy?

In our own time, the concept of happiness has moved from the private sphere to the public one. As William Davies reports in this fascinating study, a growing number of corporations employ chief happiness officers, while Google has a “jolly good fellow” to keep the company’s spirits up. Maybe the Bank of England should consider hiring a jester. Specialist happiness consultants advise those who have been forcibly displaced from their homes on how to move on emotionally. Two years ago, British Airways trialled a “happiness blanket”, which turns from red to blue as the passenger becomes more relaxed so that your level of contentment is visible to the flight attendants. A new drug, Wellbutrin, promises to alleviate major depressive symptoms occurring after the loss of a loved one. It is supposed to work so effectively that the American Psychiatric Association has ruled that to be unhappy for more than two weeks after the death of another human being can be considered a mental illness. Bereavement is a risk to one’s psychological wellbeing.

The more you chase after money, status and power, the lower your sense of worth is likely to be

It is no wonder that the notion of happiness has been taken into public ownership, given the remarkable spread of spiritual malaise around the globe. Around a third of American adults and close to half in Britain believe that they are sometimes depressed. Even so, more than half a century after the discovery of antidepressants, nobody really knows how they function. Work over which individuals have little control can heighten the risk of heart disease. (Co-operatives, by contrast, are apparently good for your health.) So-called austerity has made people sicker and driven some to death. Vastly unequal nations such as the UK and the US breed mental health problems far more than more egalitarian ones such as Sweden. Illness, absenteeism and “presenteeism” (coming into work purely to be physically present) are estimated to cost the US economy as much as $550bn (£417bn) a year.

There is evidence that a competitive ethos can trigger mental illness among the winners as well as the losers, not least in the case of sport stars. Despite the living disproof known as Donald Trump, the more you chase after money, status and power, the lower your sense of worth is likely to be. Given their pathologically upbeat culture, Americans tend to downplay their dejectedness, while the French, with their suspicion that happiness is unsophisticated, are more likely to under-report it. It is the kind of thing that cavorts at the end of piers wearing a striped jacket and red plastic nose.

Happiness is excellent for business. A cheerful worker is as much as 12% more productive. A science of human sentiments – what Davies calls “the surveillance, management and government of our feelings” – is thus one of the fastest growing forms of manipulative knowledge. So is market research into shopping, which now uses extensive face-scanning programmes in order to reveal customers’ emotional states. The more bright-eyed neuroscientists claim they are close to discovering a “buy button” in the brain.

Psychology is a well-attested way of displacing attention from social causes. After the economic crash of 2008, some psychologists concluded that the problem was not the banks but the brain. Wall Street had been afflicted by the wrong kind of neurochemicals. There was too much testosterone among traders, and too many bankers were high on cocaine. A drug was accordingly developed based on brain scans of traders that promised better decision-making. What matters in the narcissistic world of late capitalism is not what you think or do but how you feel. And since how you feel can’t be argued against, it is conveniently insulated from all debate. Men and women can now stroll around in continuous self-monitoring mode, using apps to track their changes of mood. The brutal, domineering ego of an older style of capitalism has given way to the tender self-obsession of the new. One of the few pieces of good news is that mindfulness can apparently drive you mad.

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What Davies recognises is that capitalism has now in a sense incorporated its own critique. What the system used to regard with suspicion – feeling, friendship, creativity, moral responsibility – have all now been co-opted for the purpose of maximising profits. One commentator has even argued the case for giving products away free, so as to form a closer bond with the customer. Some employers have taken to representing pay increases they give to their staff as a gift, in the hope of extracting gratitude and thus greater effort from them. It seems that there is nothing that can’t be instrumentalised. Yet the whole point of happiness is that it is an end in itself, rather than a means to power, wealth and status. For a tradition of ethical thought from Aristotle and Aquinas to Hegel and Marx, human self-fulfilment springs from the practice of virtue, and this happens purely for its own sake. How to be happy is the chief issue that ethics addresses, but “Why be happy?” is not a question it can answer.

The same tradition of thought refuses to divorce happiness from the material circumstances in which it is set. Men and women can only flourish in certain social conditions. Happiness is bound up with our activity, rather than being a private mental state. We are practical agents, not walking states of consciousness. A slave who is regularly beaten black and blue may claim that he is blissfully content, but this is probably because he knows of no other situation. In this sense, happiness is not an entirely subjective affair. You can believe that you are happy but be the victim of self-deception. Neither, however, is it objective in the sense of being a patch of stuff in the brain, as some neuroscientists seem to imagine. What they forget, as Davies asserts, is that “mental processes” are bound up with the actions of human beings embedded in social relations, guided by purposes and intentions which need to be interpreted.

Happiness for the market researchers and corporate psychologists is a matter of feeling good. But it seems that millions of individuals don’t feel good at all, and are unlikely to be persuaded to buck up by technologies of mind control that induce them to work harder or consume more. You can’t really be happy if you are a victim of injustice or exploitation, which is what the technologists of joy tend to overlook. This is why, when Aristotle speaks of a science of well-being, he gives it the name of politics. The point is of little interest to the neuroscientists, advertising gurus or mindfulness mongers, which is why so much of their work is spectacularly beside the point.

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