IELTS Academic Reading Practice Test 381

In the London of the early seventeenth century, death was a constant and visible presence. Plague returned repeatedly, killing thousands in a single summer, and ordinary diseases carried off infants and adults alike. Yet no one could say with confidence how many people lived in the city, how many died each year, or what they died of. Estimates were guesses, and the few figures that existed had been collected for purposes quite unconnected with health. It was a haberdasher with no university education who first attempted to make systematic sense of the numbers.

The source of those numbers was a weekly publication known as the bill of mortality. Beginning in the 1590s, and continuing after outbreaks of plague, the authorities in London required each parish to report the number of people who had died and the causes of death as understood by the parish clerks. These reports were printed and sold as broadsheets, and they served an administrative purpose: they allowed the government to monitor the advance of plague and to decide when restrictions should be applied or lifted. For most readers they were simply alarming news.

John Graunt was born in London in 1620 and worked in his father's trade as a draper and haberdasher, rising to become a respected member of his guild and a common councillor. He had no medical training and had gone from school into an apprenticeship rather than to a university. Yet he had access to the bills over many years, and in 1662 he published a small book with an unassuming title: Natural and Political Observations made upon the Bills of Mortality. It is now regarded as a founding work of demography and of epidemiology, although neither word existed in his lifetime.

Graunt's method was to compile the bills from successive years into tables and then to look for patterns within them. The records were unreliable in particular ways. The causes of death were assigned by parish clerks who had no medical knowledge. Some parishes, especially in the growing suburbs, were omitted from the returns altogether, so that the total number of deaths was certainly too low. Graunt did not throw the figures away on that account. Instead he distinguished what he called 'positive' counts from matters that could only be estimated.

From these materials he drew several conclusions. Comparing deaths with baptisms in the same parishes, he calculated that the population of London was growing steadily, largely through migration from the countryside rather than through the excess of births over deaths. He produced one of the earliest estimates of the city's population, and although modern historians consider it too low, the reasoning was sound. He also tabulated deaths by age. The bills did not record ages directly, but Graunt inferred them from causes such as 'teeth' and 'convulsions', which were then associated with infancy.

His most famous observation concerned the ratio of male to female births. The bills showed a small but consistent excess of boys over girls, and Graunt wondered why. He considered the hazards of childbirth and the demands of war and seafaring, and concluded that a slightly higher number of male births was necessary to balance the greater mortality of men. Whether or not his explanation was correct, the observation was important: he had identified a regularity that seemed to hold year after year, and he treated it as something requiring explanation rather than as an accident.

Graunt's book was read widely and admired by the intellectual circles of the day. He was proposed for membership of the newly founded Royal Society, and the king, Charles II, intervened personally to waive the usual requirements so that he could be admitted. The diarist Samuel Pepys recorded buying the book and reading it with great interest. The second edition of 1665, published as plague was once again sweeping the city, added further material, and the bills themselves became objects of increasing public attention.

Not everyone was convinced. Some contemporaries doubted that a tradesman could have written such a work and suggested that a friend must have helped him; the claim has never been substantiated. Others objected that the bills were far too crude to support the conclusions drawn from them. Graunt acknowledged the weaknesses himself, and historians now recognise that several of his estimates were mistaken. His significance lies less in the accuracy of his figures than in his approach: the assumption that human populations, however disorderly they appear, obey regular patterns that can be discovered by careful counting.

The tradition he began developed rapidly. His friend William Petty extended similar methods to the study of population, and in 1693 the astronomer Edmond Halley used parish records from the city of Breslau to construct the first proper life table, which showed the probability of surviving to each age. That device underlies every modern calculation of life expectancy. The bills of mortality continued to be published into the nineteenth century, when they were replaced by a national system of registration recording each death with age and certified cause.

Graunt's own life ended in modest circumstances. He had prospered for a time but suffered heavy losses in the Great Fire of London in 1666 and in later misfortunes, and he died in 1674. His habit of testing claims against counted evidence, and stating plainly where the evidence ran out, remains recognisably the method of public health today.

Newspapers regularly report that life expectancy has risen again, or that it has stalled, and the figure is treated as a summary of how well a country is doing. Yet the number is not a prediction about any individual, nor a simple average of the ages at which people die. It is a statistical construction with a long history, a specific meaning and some well-known limitations, and understanding how it is produced makes its use, and its frequent misinterpretation, much easier to follow.

The basic tool is the life table, a device that describes what would happen to a group of people if they were exposed throughout their lives to the death rates observed in a particular year. The table begins with a hypothetical group, usually 100,000 births, and applies the probability of dying at each age. If, in the year in question, five in every thousand people aged 60 died before reaching 61, the table assumes that five per thousand in its imaginary cohort do the same. Carrying this forward from birth to the oldest ages produces a curve of survivors, from which the average number of years lived can be calculated. That average is life expectancy at birth.

The crucial point is that the figure describes a hypothetical population, not a real one. Nobody actually experiences one year's death rates for a whole lifetime. If mortality continues to fall, as it generally did through the twentieth century, real people will live longer than the table predicts, because they will benefit from improvements that had not yet happened when the table was drawn up. This is why life expectancy at birth has repeatedly been a poor forecast: demographers have often underestimated future gains, and projections made decades ago for today's populations have generally proved too pessimistic.

A second feature is that the measure is unusually sensitive to deaths in the first year of life. A death in infancy removes almost all of a person's potential years. A country with high infant mortality will therefore show a low life expectancy even if adults commonly reach old age. This explains why some historical populations appear to have had appallingly short lives: in seventeenth-century Europe, a substantial proportion of children died before their fifth birthday, which pulls the average down sharply. An adult who survived childhood might reasonably expect to live into their fifties or sixties. The commonly quoted figure of '35 years' for earlier centuries describes the experience of a population in which many died young, not the typical lifespan of an adult.

Because of this sensitivity, epidemiologists often prefer a different measure. Life expectancy at age 65, or at age 15, excludes the years already lived and is not affected by infant deaths. Some researchers also calculate 'healthy life expectancy', which attempts to count only the years lived in good health rather than merely the years lived. The World Health Organization publishes this figure for its member states, and the gap between total and healthy life expectancy, which in many countries is around a decade, is a more revealing indicator of the burden of chronic illness than the headline number.

Another distinction is between period and cohort measures. A period life table, the kind produced annually by national statistics offices, applies one year's death rates to the hypothetical group. A cohort table follows an actual group of people born in the same year throughout their lives, which requires waiting decades but reflects real experience. During the COVID-19 pandemic, period life expectancy fell in many countries, and commentators interpreted this as a catastrophic loss of lifespan. In part it was a real and serious loss of life. In part, however, the fall reflected the fact that a period measure attributes to everyone alive the elevated mortality of a single exceptional year, even though most of those people will not experience such conditions again.

Comparisons between countries carry further complications. National averages conceal enormous differences between regions and between social groups. In the United Kingdom, for instance, life expectancy in the most deprived areas is several years lower than in the most affluent, and the gap widened during the 2010s. A single national figure can therefore be technically accurate and substantively misleading, appearing to describe a uniform population that does not exist. The same applies to countries at very different income levels, where clean water, vaccination and treatment for common infections explain far more of the difference than any feature of the health service.

There is also the problem of what counts as a death. Countries with good civil registration and medical certification of causes of death produce reliable data; countries with incomplete registration do not, and their figures are modelled by international agencies using survey data and estimates. The uncertainty attached to such figures can be considerable, and a difference of a year or two between two countries may be smaller than the margin of error. Readers should be cautious about league tables in which nations are ranked by small differences.

None of this means the measure is discredited. Life expectancy remains one of the most powerful and comparable indicators of population health ever devised, and its broad trends over the past century and a half, the near doubling of average lifespans in many countries, are among the most important facts about modern society. But it is a summary, not a verdict. Used with awareness of what it does and does not capture, it tells us a great deal; quoted as though it were a prediction of how long we will each live, it misleads.

Few goals in medicine seem as obviously desirable as prolonging life. Death is generally regarded as the worst outcome, and any treatment that delays it is assumed to be a good. Research funders increasingly speak of extending healthy lifespan as a target in its own right, and the prospect of slowing ageing itself, once dismissed as fantasy, is now discussed in serious journals. I want to ask whether a longer life is always worth having, not because I doubt the value of health, but because the question is less straightforward than the slogans suggest.

The strongest argument for extension rests on a simple observation: the alternative to living longer is dying sooner, and very few people, given the choice, would prefer the second. The gains of the past century and a half have been enormous. Average lifespans in many countries roughly doubled, mostly because infants stopped dying of infections and because clean water, vaccination and antibiotics transformed the experience of ordinary illness. Almost nobody seriously argues that this was a mistake. If further gains are possible, the burden of proof would seem to lie with those who would refuse them.

Yet the case becomes less clear when the question shifts from preventing early death to extending the maximum span. The relevant distinction is between lifespan and healthspan, the period lived free of serious disease and disability. Most people would not regard an extra decade of severe dependency as a benefit, and it is not obvious that research which extends life without compressing illness is worthwhile. Some gerontologists argue that the two cannot be separated and that delaying ageing postpones disability together with death. That may prove correct, but it is a claim about the future rather than an established result, and it cannot by itself justify every intervention that lengthens life.

The economic objections are also more substantial than they first appear. It is often said that longer lives would bankrupt pension systems and health services, and this argument is usually presented badly, as though people who live longer contribute nothing. In fact older people work, pay taxes, care for grandchildren and volunteer, and the costs of an ageing population have been overstated in many public debates. Nevertheless, the timing of the costs and the benefits is genuinely awkward. The savings that would follow from delaying disability may arrive decades after the expenditure that produced them, and governments are not famous for patience.

A further concern is what might be called the problem of pace. Human institutions, careers and relationships are organised around a rough expectation of how long a life will last. If people could expect to live to 120 in good health, the patterns of education, work, marriage and inheritance would all have to change, and it is not clear that they could change fast enough to keep up. A society in which a few wealthy people live considerably longer than everyone else would be a new kind of inequality, and one far harder to correct than the inequalities we currently argue about.

Against this, it is worth remembering that similar anxieties greeted earlier increases in lifespan, and they did not come true. When average lives rose from forty to seventy, commentators predicted the collapse of the family, the ruin of the economy and the exhaustion of the countryside; what actually happened was the invention of retirement, the expansion of education and a great deal of unanticipated adaptation. The pessimists were not right in detail; they were wrong in spirit. There is no reason to assume that our own generation has suddenly become incapable of adjustment.

Nor should we overlook how much of the debate is really about distribution rather than duration. The question of whether anyone should live to 120 is less urgent than the question of why a man in one part of a city can expect a decade less of life than his neighbour a few streets away. Resources devoted to speculative extension are resources not devoted to the unglamorous work of reducing smoking, improving housing, treating hypertension and ensuring that existing knowledge reaches the people who need it. A civilisation that could add years to the lives of the many but chooses to chase immortality for the few has its priorities badly arranged.

So where does that leave the original question? I do not think a longer life is always a good thing, because the value of an extra year depends entirely on what it contains and on who gets it. A year of pain and isolation is not a gift, and an extra decade enjoyed by the comfortable while others lose a decade at the bottom of the same city is hardly progress. But I also reject the view that the pursuit of longer life is vain or selfish. The history of the last century suggests that, when the extension of life is pursued alongside the reduction of needless suffering, both can advance together.

What follows is a principle rather than a policy: extend life, but insist that the extension is enjoyed, and that it is shared. Research into ageing should be judged by its effect on years of healthy life across a population, not by the maximum age recorded in a laboratory. Politicians who speak of longevity should be asked what they are doing about the gap in health between rich and poor and about the loneliness that makes extra years a burden. And those of us who hope to live longer should be honest that we are seeking not simply more time but more of what makes time worth having.