Reading: meaning and structure

The origins of writing in Mesopotamia

Writing appears to have been invented independently in several parts of the world, but one of the earliest known systems developed in southern Mesopotamia, in what is now Iraq, more than five thousand years ago. Its origins were surprisingly practical. The first inscriptions were not poems, laws or histories but administrative records, kept by officials of temples and cities who needed to track grain, livestock, labour and other goods.

Before writing, accountants in the region used small clay tokens of different shapes to represent quantities of goods. Many scholars believe that marks pressed into clay to stand for these tokens gradually developed into signs. Early signs were often pictures of the thing counted, combined with marks for numbers. Over the following centuries, the signs became more abstract and were made by pressing a reed into wet clay, producing the wedge-shaped marks that give cuneiform its name, from the Latin word for wedge.

A major step came when scribes began to use signs for their sounds as well as their meanings. This allowed them to write names, grammatical endings and eventually whole sentences of spoken language. Cuneiform was later adapted to write many different languages across the Near East and remained in use for around three thousand years.

Learning the system was demanding, since it used hundreds of signs. Scribes trained for years in schools, copying lists of signs and model texts, and literacy remained limited to a small professional group. Much of what we know about these schools comes from the clay tablets themselves, which survived in large numbers because baked or sun-dried clay is extremely durable.

Life at hydrothermal vents

Until the late 1970s, most biologists assumed that almost all life on Earth depended, directly or indirectly, on energy from the Sun. Plants and algae capture sunlight through photosynthesis, and animals eat the plants or one another. The deep ocean floor, far below the reach of light, was expected to support only sparse life, fed by organic matter drifting down from the surface.

That view changed when scientists using a submersible explored hot springs on the floor of the eastern Pacific. Around these hydrothermal vents, where seawater heated by volcanic activity pours out of the sea floor rich in dissolved minerals, they found dense communities of animals, including giant tube worms, clams and crabs. The basis of these communities is not photosynthesis but chemosynthesis. Certain bacteria obtain energy from chemical reactions involving compounds such as hydrogen sulphide in the vent fluid, and use it to produce organic matter. Some vent animals feed on the bacteria; others, like the tube worms, house them inside their bodies and depend on them for nourishment.

The discovery had consequences beyond marine biology. It showed that whole ecosystems can run on chemical energy, independent of sunlight, and it encouraged speculation that life on Earth may have begun in a similar setting. It has also influenced the search for life elsewhere. Several moons in the outer solar system are thought to have oceans beneath their icy surfaces, and if those oceans have hydrothermal activity, they might provide conditions in which life could exist.

Vent communities are not entirely cut off from the sunlit world, however: many of the animals depend on oxygen dissolved in seawater, which was produced by photosynthesis near the surface.

Learning by testing

Many students prepare for examinations by rereading their notes and highlighting important passages. These strategies feel productive: as the material becomes familiar, students gain a sense that they know it. Research in cognitive psychology suggests, however, that familiarity is a poor guide to what will be remembered later, and that some less comfortable strategies are considerably more effective.

One of the best supported is retrieval practice, which means trying to recall information from memory, for example by answering practice questions or writing down everything one can remember about a topic without looking at notes. In many experiments, students who spent part of their study time testing themselves remembered more a week later than students who spent the same time rereading, even when the rereading group felt more confident. The act of retrieving information appears to strengthen the memory itself, and it also shows learners which parts they have not yet mastered.

A second strategy is spacing. Studying a topic in several shorter sessions spread over days or weeks generally produces better long-term retention than the same total time concentrated in a single session, a practice often called cramming. Cramming can be effective for a test the next morning, but much of the material is soon forgotten.

Both strategies share a feature that makes them unpopular: they feel harder. Recalling information with effort, and returning to material after partly forgetting it, produces more mistakes during study. Psychologists sometimes describe such strategies as desirable difficulties, because the effort that makes them uncomfortable is closely linked to the benefits they bring.

Compact cities

Urban planners have long debated how densely cities should be built. In many countries, the growth of car ownership in the twentieth century encouraged low-density suburbs of detached houses, separated from shops and workplaces. More recently, many planners have argued for more compact development, in which homes, jobs and services are closer together.

Supporters of compact cities point to several advantages. When destinations are close, more trips can be made on foot, by bicycle or by public transport, which reduces traffic and emissions from vehicles. Public transport itself becomes more viable, because enough passengers live within reach of each station to justify frequent services. Compact development also uses less land, leaving more countryside and farmland undeveloped, and it can make the provision of water, sewers and other infrastructure cheaper per household.

Critics raise several objections. Higher density can mean smaller homes and less private outdoor space, which many families value. If new buildings are not accompanied by parks, schools and health services, existing facilities may become overcrowded. In some cities, restrictions that prevent building upward or adding homes to existing neighbourhoods have pushed housing costs up, and critics argue that denser building alone does not guarantee affordability unless enough homes are built.

Most planners now see the question less as a choice between two models than as a matter of design. A well-planned neighbourhood of terraced houses and low apartment buildings can achieve much of the benefit of density without towering blocks, provided that it includes green space and good public transport.

Photography and painting

When photography became practical in the middle of the nineteenth century, some observers predicted that painting would soon be obsolete. A camera could record a face or a landscape with a precision that few painters could match, and in far less time. In one field the prediction was partly correct: many artists who had made a living painting small portraits found their customers turning to photographers, whose portraits were cheaper and quicker to produce.

For painting as a whole, however, the effect was more complicated. Freed from the need to provide an accurate record, some painters began to explore what the camera could not do. They experimented with colour, brushwork and the expression of feeling, and later movements moved further and further from realistic representation. Historians caution against treating photography as the single cause of these changes, which also had roots in new ideas about art, new materials and the changing market for paintings, but it is widely seen as one important influence.

The relationship also ran the other way. Painters used photographs as references, studying poses, cloud formations or the movements of animals that were too quick for the eye to follow. Photographs of horses in motion, for example, showed that earlier paintings had depicted galloping legs in positions that horses never actually adopt. Photographers, for their part, often imitated the composition and lighting of paintings in an effort to have their work accepted as art.

Within a few decades, it was clear that the two media would coexist, each influencing the other, and that the camera had changed the questions painters asked rather than ending their art.

The discovery of penicillin

Put the sentences in the right order. Topic: The discovery of penicillin.

Prices in a market

Put the sentences in the right order. Topic: Prices in a market.

How glaciers shape valleys

Put the sentences in the right order. Topic: How glaciers shape valleys.

Reading to young children

Put the sentences in the right order. Topic: Reading to young children.

The Bauhaus

Put the sentences in the right order. Topic: The Bauhaus.

Testing a new medicine

Put the sentences in the right order. Topic: Testing a new medicine.

The shipping container

Put the sentences in the right order. Topic: The shipping container.

How tsunamis form

Put the sentences in the right order. Topic: How tsunamis form.

Magna Carta

Put the sentences in the right order. Topic: Magna Carta.

Recommendation systems

Put the sentences in the right order. Topic: Recommendation systems.

Mangrove forests

Put the sentences in the right order. Topic: Mangrove forests.

Structured interviews

Put the sentences in the right order. Topic: Structured interviews.

Roman roads

Roman roads are often admired as feats of engineering, built with layers of stone and gravel and laid out in long straight lines. It is easy to forget why the state invested so heavily in them. The roads allowed armies to move quickly between provinces, and official messengers used them to carry orders and reports. Trade and private travel certainly benefited, but these were largely side effects of a network designed to hold a large empire together.

App-based work

Supporters of app-based work describe it as freedom: drivers and couriers choose their own hours and can work for several platforms at once. This picture is not false, but it is incomplete. Flexibility is worth most to those who have other income and can turn down poorly paid jobs. For workers who depend entirely on the apps, the freedom to log off can mean the freedom to earn nothing, and decisions about pay are made by software they cannot question.

Driving on Mars

Robotic rovers on Mars cannot be steered in real time from Earth. Depending on where the two planets are in their orbits, a radio signal takes from a few minutes to more than twenty minutes to travel each way. Engineers therefore send a set of instructions once a day, and the rover carries them out on its own, using cameras and software to avoid hazards. This is one reason rovers travel slowly: a mistake could leave a vehicle stuck far beyond the reach of any repair.

Reading on screens

In several studies, students read the same texts either on paper or on screens and then answered questions. For short, simple passages, the medium made little difference. With longer and more complex texts, however, readers on paper tended to understand slightly more, and screen readers were more likely to overestimate how well they had understood. One explanation is that people associate screens with quick, shallow reading, such as checking messages, and carry that habit over to study.

Early modern spelling

Readers of sixteenth-century English texts are often struck by how freely words were spelled. The same writer might spell a word in two different ways on a single page, and printers sometimes added or removed letters simply to fit a line. Spelling began to settle only gradually, helped by the spread of printed books and later by influential dictionaries. Variation, in other words, was not a sign of carelessness but a normal feature of the written language at the time.

The octopus nervous system

Octopuses have a nervous system unlike that of any vertebrate. Of their roughly five hundred million neurons, a majority are located not in the brain but in the arms. Each arm can respond to touch and taste and can carry out some movements without direct instruction from the brain, which may explain how an octopus coordinates eight flexible limbs at once. Researchers studying this arrangement hope it may inspire new designs for soft robots.

Fog nets

In some coastal deserts, rain is rare but fog rolls in from the sea on many mornings. Communities in such places have experimented with large mesh nets stretched between poles. As fog passes through, tiny droplets collect on the mesh, merge and run down into gutters and storage tanks. The water gathered is modest, but it can supply drinking water or small gardens where no other source exists. The method works only where fog is frequent and the wind carries it reliably through the nets.

Music and dementia

Care staff often notice that people with advanced dementia, who may struggle to recognise relatives, can still sing songs they learned decades earlier. Memory for music appears to rely partly on brain areas that are damaged relatively late in the disease. Some care homes now use personal playlists, built with families, to calm distress and prompt conversation. Music does not slow the disease, but it can offer moments of connection when other forms of communication have become difficult.

Machine translation

Machine translation has improved enormously, and for everyday purposes such as reading a menu or a news article it is often good enough. It would be a mistake, however, to conclude that human translators are no longer needed. Legal contracts, medical instructions and literature all depend on precise choices about tone and meaning, and an error that seems small can have serious consequences. The sensible approach is to treat the software as a fast first draft that a skilled person checks.

Marks and comments

In one classroom study, students received either a mark alone, comments alone, or a mark with comments on their written work. Students who received comments alone improved most on the next assignment. Those who received a mark with comments improved about as little as those given only a mark. The researchers suggested that once a grade is visible, students tend to focus on it and pay less attention to advice about how to improve.

Carbon taxes

A tax on carbon emissions is often presented as the most efficient climate policy, because it lets firms find the cheapest ways to cut pollution. Economists who favour it rarely deny that it has a weakness. Fuel and heating make up a larger share of spending for poorer households, so a carbon tax can take a bigger bite from their budgets. For this reason, many proposals return the money raised to households as equal payments, which can leave lower-income families better off overall.

Railway time

Until the mid-nineteenth century, towns in Britain kept their own local time, set by the position of the sun. Clocks in the west of the country ran several minutes behind those in London. This caused few difficulties when travel was slow, but railway timetables became confusing when every station kept a different time. Railway companies began to adopt London time across their networks in the 1840s, and the wider use of a single standard time followed.

Where food is lost

Discussions of food waste often focus on households throwing away leftovers. In wealthier countries, this is indeed a large share of the problem. In many lower-income countries, however, most loss happens much earlier, between the farm and the market, because of poor storage, a lack of refrigeration and slow transport. Effective policy therefore depends on where in the chain food is being lost, and solutions that work in one country may matter little in another.

Peer review

Before a research paper is published in most academic journals, it is sent to other experts in the field, who assess its methods and conclusions. This process, known as peer review, is meant to catch errors and weak arguments. It is not a guarantee of truth. Reviewers rarely repeat the experiments themselves, and they can miss mistakes, especially when data are not shared. Published findings are best seen as claims that have passed a first check, not as settled facts.

Spring tides

Most coasts experience two high tides and two low tides roughly every day. The main cause is the Moon's gravity, which pulls the oceans into a slight bulge on the side of the Earth facing it. A second bulge forms on the opposite side, and as the Earth rotates, each stretch of coast passes through both. The Sun has a smaller effect, but when Sun and Moon line up, their combined pull produces especially large tides, known as spring tides.