Economic growth and sustainability

The business (trade) cycle is the fluctuation of real GDP around its long-run trend over time, passing through distinct phases.

In a boom (peak), real GDP grows rapidly, unemployment is low, and inflation tends to rise as the economy approaches or exceeds capacity (a positive output gap). In the slowdown/downturn, growth slows. In a recession (slump/trough), real GDP falls (often defined as two consecutive quarters of negative growth), unemployment rises, and inflation is low (a negative output gap). In the recovery, growth resumes and the economy moves back toward the trend. The cycle is driven by fluctuations in aggregate demand — changes in confidence, the volatile multiplier-accelerator interaction, asset bubbles and external shocks.

Automatic stabilisers are features of the tax and benefit system that automatically dampen these fluctuations, without any deliberate change in government policy. In a boom, rising incomes mean people pay more tax (especially under a progressive system, as they move into higher bands) and claim fewer benefits; this automatically restrains the growth of disposable income and AD, cooling the boom and limiting inflation. In a recession, falling incomes mean people pay less tax and claim more benefits (e.g. unemployment benefit); this automatically supports disposable income and AD, cushioning the fall in output and employment.

The key advantage of automatic stabilisers is that they act immediately and automatically, with no time lag — unlike discretionary fiscal policy, which requires recognition, decision and implementation. They therefore provide a built-in, self-acting moderating force on the cycle, reducing the size of both booms and slumps. However, they only dampen the cycle rather than eliminate it, and very strong stabilisers (high taxes/generous benefits) could blunt incentives. So automatic stabilisers smooth the business cycle, complementing (but not replacing) active stabilisation policy.

Inclusive growth is growth whose benefits are widely and fairly shared (reducing inequality); sustainable growth is growth that can be maintained without depleting resources or harming the environment for future generations. The claim that growth cannot be both suggests an inherent conflict, which must be tested.

The case that there is a conflict. Achieving inclusivity may require rapid growth to raise the incomes of the poor quickly, but rapid, resource-intensive growth can cause pollution, resource depletion and climate change — undermining sustainability. Conversely, green policies needed for sustainability — such as carbon taxes or higher energy prices — can be regressive, hitting the poor hardest (a larger share of their income), which harms inclusivity. Developing economies in particular may feel forced to choose between lifting people out of poverty (inclusive growth, often via fossil fuels and heavy industry) and protecting the environment (sustainability). On these grounds the two goals can pull in opposite directions.

The case that they can be combined. The conflict is not inevitable. Green investment — in renewable energy, public transport and energy efficiency — can create jobs and incomes for poorer groups (inclusive) while cutting emissions (sustainable). Investment in education, healthcare and clean infrastructure raises the productivity and opportunities of the poor and supports cleaner long-run growth. Carbon-tax revenue can be recycled to compensate poorer households (e.g. via transfers or 'green cheques'), removing the regressive effect. Many policies — clean public transport, insulation programmes, renewable jobs — are both inclusive and sustainable. So with the right policy design, the goals can be complementary rather than competing.

Judgement. Economic growth can be both inclusive and sustainable, but it does not happen automatically — it requires deliberate, well-designed policy. Left to the market, growth may be neither (rising inequality and environmental damage). There are real tensions — especially the regressive impact of some green policies and the speed-vs-sustainability dilemma for developing economies — so the goals can conflict in the short run. However, policies such as green investment with revenue recycling and human-capital spending targeted at the poor can deliver growth that is both inclusive and sustainable over the long run. The most defensible conclusion is that the two goals are not fundamentally incompatible: the claim is too pessimistic, but achieving both requires careful policy that manages the genuine trade-offs, rather than relying on growth alone.

Although the economy has achieved positive real GDP growth, judging whether the growth has been 'good' requires looking at its distribution and sustainability, not just its rate.

Not inclusive. Because the richest 10% captured most of the gains, the growth has not been inclusive — the benefits have not been widely or fairly shared, so inequality has likely risen and the living standards of the poor may have improved little despite higher GDP. Average growth has masked an uneven distribution.

Not sustainable. Because carbon emissions have risen sharply, the growth has imposed significant negative externalities (pollution and contribution to climate change) and may be depleting resources — so it is environmentally unsustainable, harming future generations and possibly the economy's own long-run capacity.

Assessment. By modern standards, this growth is not 'good': it is neither inclusive (gains concentrated among the rich) nor sustainable (rising emissions). Higher real GDP alone is not enough — 'good' growth should also be fairly shared and environmentally sustainable. To improve, the government could pursue inclusive policies (education, progressive taxes/transfers targeting the poor) and green policies (carbon taxes/permits, renewable investment), ideally combining them (e.g. green jobs, recycled carbon-tax revenue) so that future growth raises welfare broadly without environmental damage.

Actual growth is an increase in the real output actually produced; potential growth is an increase in productive capacity (a rightward shift of LRAS). Policies to raise each differ, and their relative importance depends on the economy's situation.

The case for prioritising potential growth. Only potential growth raises the economy's long-run capacity, so it is the source of sustained rises in living standards. Supply-side policies — investment in education, training, infrastructure and technology — shift LRAS right, allowing higher output without inflation and improving competitiveness and structural unemployment. Without rising potential output, actual growth eventually hits a capacity ceiling and merely causes inflation. For the long run, raising potential output is therefore essential.

The case for prioritising actual growth. In a recession with a large negative output gap, the immediate problem is deficient demand — actual output is well below potential, with high unemployment. Here, demand-side policy to raise actual growth (using spare capacity) is more urgent: it puts idle resources back to work quickly, reducing unemployment and its costs. Raising potential output is pointless if the existing capacity is unused — supply-side policy is also slow. So in a slump, actual growth matters most.

Judgement. Neither is universally more important — it depends on the economy's position. In the short run, especially in a recession with spare capacity, policies to raise actual growth (demand-side) are more important, to use idle resources and cut unemployment. In the long run, and when the economy is near full capacity, policies to raise potential growth (supply-side) are more important, because they are the only sustainable, non-inflationary source of higher living standards. The most defensible conclusion is that they are complementary: a government should raise potential output over the long run while ensuring adequate demand so that capacity is actually used — getting the balance right according to where the economy is in the cycle.