IELTS Academic Reading — Practice Test 12

The phrase 'sharing economy' entered common use around 2010 to describe a wave of businesses built on a simple idea: that digital platforms could let people rent out what they already owned — a spare room, a car, an hour of their time — to strangers who needed it. Enthusiasts hailed it as a quiet revolution. Instead of everyone buying their own drill or booking their own hotel room, resources that once sat idle could be shared, cutting waste and putting money in ordinary pockets. A decade on, the reality is more complicated. Two of the sector's giants, ride-hailing and short-term letting, have reshaped daily life in cities around the world, and not always in the ways their founders promised.

The original case for these platforms was genuinely attractive. A car spends most of its life parked; a spare room earns nothing while it stands empty. By matching these dormant assets with people willing to pay for them, the argument went, the platforms squeezed more value out of what already existed, without the environmental cost of building or manufacturing anything new. For hosts and drivers, the extra income could be significant, and for consumers the services were often cheaper and more convenient than the established alternatives. Crucially, the whole system depended on trust between strangers, which the platforms manufactured through ratings and reviews — a feature that distinguished them from the informal arrangements that had always existed.

Yet the effects on cities have frequently confounded these expectations. Ride-hailing was expected to reduce car use, on the assumption that easy access to a hired car would persuade people to give up their own. Studies in several large cities suggest the opposite has often happened. Rather than replacing private cars, the services have drawn passengers away from buses, trains and bicycles, adding vehicles to already crowded streets. Because drivers spend a large share of their time cruising between fares without a passenger, each trip can generate more traffic than the private journey it replaces. In a number of cities, the arrival of ride-hailing has coincided with falling use of public transport and rising congestion — the reverse of what was advertised.

Short-term letting has provoked an even sharper backlash. In the most visited cities, landlords discovered they could earn far more by renting to a stream of tourists than to long-term residents. Apartments that would once have housed local families were converted, sometimes whole buildings at a time, into unofficial hotels. The consequences fell hardest on housing: as flats were withdrawn from the ordinary rental market, supply tightened and rents climbed, pushing residents out of the very central neighbourhoods that tourists came to see. Districts once full of permanent inhabitants began to hollow out, their shops and services reoriented towards short-stay visitors. What looked, on each platform, like an individual homeowner earning a little extra had become, in aggregate, a force reshaping who could afford to live in a city.

The platforms have also transformed the nature of work. Drivers and couriers are typically classified not as employees but as independent contractors, free to work when they choose. For some, that flexibility is precisely the appeal, fitting paid work around study or family. For others, it means the insecurity of unpredictable earnings, no sick pay and no pension, while an app rather than a human manager dictates the terms. This ambiguity — are these workers running their own small businesses, or are they employees in all but name? — has become one of the most contested questions the sector raises, and courts in several countries have reached opposite conclusions.

Cities have not stood by. Faced with rising rents and clogged roads, many have moved to regulate what they once welcomed. Some have capped the number of nights a home may be let each year, or required hosts to register and pay the taxes that hotels pay; others have limited the number of ride-hailing licences or imposed a levy on each journey. The platforms have resisted such measures fiercely, arguing that they stifle innovation and punish ordinary people earning a supplementary income. But the trend is clear: the era in which these companies could expand faster than governments could respond is drawing to a close.

It would be wrong to conclude that the sharing economy has failed. Millions use its services daily, and the convenience it offers is real. The lesson of its first decade is subtler: that a technology which is plainly beneficial to the individual using it can, when adopted at scale, produce collective effects that no single user intended. A spare room let to a visitor harms no one; ten thousand of them can price a neighbourhood out of reach. Judging these platforms means looking past the tidy logic of the individual transaction to the messier arithmetic of the city as a whole.

Every time a scientist draws a general law from particular observations, they perform an act of faith so familiar that it usually goes unnoticed. Having watched the sun rise on every recorded morning, we conclude that it will rise tomorrow; having found that every sample of a metal expands when heated, we announce a law that all samples will. This movement from the observed to the unobserved, from some to all, is called induction, and it is the engine of empirical knowledge. Without it, the accumulated results of experiment would tell us only about the particular objects examined, never about the world in general. The whole edifice of natural science, from the humblest measurement to the grandest theory, rests on the assumption that patterns found so far will hold in cases not yet seen. The trouble is that this assumption turns out to be extraordinarily difficult to justify.

The difficulty was set out with lasting force by the eighteenth-century Scottish philosopher David Hume. Why, Hume asked, are we entitled to expect the future to resemble the past? Not, he argued, on grounds of pure logic: there is no contradiction in supposing that the sun might fail to rise, or that bread might one day cease to nourish. Such things would surprise us enormously, but a surprise is not a logical impossibility. Nor, Hume continued, can the expectation be justified by experience, for that is precisely what is in question. To say that induction has worked well until now, and so may be trusted, is to reason inductively — to assume that the past reliability of the method guarantees its future reliability. The argument thus takes for granted the very principle it is meant to establish. Hume concluded that our confidence in induction is a matter of habit, not of reason: we generalise because our minds are built to, not because we can show that we are right to.

It is tempting to think this a mere philosopher's puzzle, easily brushed aside by pointing to science's spectacular success. But the objection bites deeper than that. The success of science is itself a fact about the past — about predictions that have so far come true — and to infer from it that science will go on succeeding is to make exactly the inductive leap whose validity is in doubt. Every attempt to defend induction by its track record runs into the same wall: it can only work by assuming what it sets out to prove. Nor does it help to retreat to probability and claim that induction, while not certain, is at least likely to work. For the same question returns one level up: what justifies the belief that what has been probable in the past will remain probable in future? The circularity is not a flaw in one particular defence of induction; it appears to infect them all.

One of the boldest responses came from the philosopher Karl Popper, who argued that science does not, and need not, rely on induction at all. Scientists, on his account, do not cautiously accumulate confirming instances; they propose bold conjectures and then try to refute them. A universal law can never be proved by any number of positive cases, but it can be decisively disproved by a single negative one: no quantity of white swans establishes that all swans are white, yet one black swan settles the matter. Science advances, Popper claimed, not by proving theories true but by weeding out the false, and this process of falsification is a matter of ordinary deductive logic, which needs no inductive assumption. The problem of induction, on this view, is not solved so much as sidestepped: it was never really science's problem to begin with.

Popper's escape has struck many as too neat. If a theory has survived every attempt to refute it, we naturally treat it as more trustworthy than a rival that has not been tested, and we rely on it to build bridges and design vaccines. But 'more trustworthy' is a claim about future performance, and it is hard to see how it can be defended without some inductive step of the very kind Popper claimed to avoid. To prefer a well-tested theory because it has passed its tests is, critics object, to assume that past testing bears on future reliability — which is induction under another name. Popper may have described how theories are eliminated, but he seems not to have explained why we are entitled to lean on the survivors.

A different strategy accepts that induction cannot be proved reliable and asks a more modest question: can its use nonetheless be justified? The philosopher Hans Reichenbach suggested that even if we cannot show induction will work, we can show that if any method will work, induction will. Should the world contain regularities to be found, a policy of projecting observed patterns is bound, eventually, to find them; should it contain none, no method could succeed anyway, so we lose nothing by trying. On this pragmatic view, induction is defended not as a guaranteed route to truth but as a rational bet — the best strategy available in a world whose orderliness we cannot establish in advance. Whether such a 'vindication' truly answers Hume, or merely changes the subject, remains disputed.

What is striking is that, after more than two centuries, no response commands general agreement. Some philosophers regard the problem as genuinely unsolved and perhaps unsolvable, a permanent scandal at the foundations of knowledge. Others suspect that it rests on an impossibly high standard — a demand for a kind of justification that no form of reasoning, deductive logic included, could ever meet, so that induction is no worse off than anything else. What almost everyone concedes is that the practice of science is untouched by the debate: laboratories do not fall silent because a philosopher cannot justify the inference they depend on. The problem of induction is not a reason to abandon inductive reasoning, which we could not do if we tried. It is, rather, a lasting reminder of how little we can prove about the sources of what we most confidently claim to know.