One of the most influential theories in macroeconomics over the past five decades is the Ricardian Equivalence theory, reformulated by economist Robert Barro in 1974 based on an idea first introduced nearly a century and a half earlier by David Ricardo. The theory is built on a deceptively simple yet far-reaching proposition: if a government finances its spending through borrowing rather than taxation, rational citizens will anticipate that today’s debt will eventually be repaid through higher future taxes. Consequently, they will increase their savings today, offsetting the government’s fiscal stimulus. In this framework, public borrowing and taxation become economically equivalent.

 

This idea has profoundly influenced modern fiscal thinking and has become one of the intellectual foundations for advocates of fiscal discipline and limited government borrowing. Yet an important question remains: Does this theory truly describe the functioning of modern economies? Are all forms of public debt really the same?

 

I believe the answer is no. The elegance of the theory lies in its mathematical rigor, but it rests on a set of assumptions that rarely hold in the real world. It assumes that households are perfectly rational, make decisions across generations, care about the welfare of their grandchildren as much as their own, have unrestricted access to credit and savings markets, operate in perfect capital markets, trust governments to manage debt efficiently, and can accurately anticipate future taxation. If all these conditions held, Barro’s conclusion would be persuasive. The real economy, however, is far more complex than theoretical models.

 

More importantly, the principal weakness of the theory is not its assumptions alone, but its failure to distinguish between two fundamentally different types of public debt. Not all debt is created equal.

 

Borrowing to finance public-sector wages, consumer subsidies, and recurrent operating expenditures is fundamentally different from borrowing to build a seaport, a power plant, a railway, a university, a telecommunications network, a green hydrogen project, or digital infrastructure. In the first case, the current generation consumes resources while leaving future generations to pay the bill. In the second, debt finances productive assets that benefit both current and future generations.

 

The critical question, therefore, is not how much debt has been accumulated, but rather what that debt has financed. In accounting, financial health is not assessed by examining liabilities alone; assets must also be considered. The same principle applies to public finance. If a government borrows one billion dinars to finance a project that raises GDP, creates jobs, and generates additional tax revenues for decades, future generations inherit not only the debt but also the productive asset that helps repay it.

 

By treating debt and taxation as equivalent, Barro’s framework overlooks one of the most important elements of a nation’s balance sheet: public assets. This criticism is hardly new. Ironically, David Ricardo himself, the economist whose name is attached to the theory, was not convinced that it accurately described actual human behavior. He regarded it more as a theoretical possibility than an empirical reality.

 

Likewise, Adam Smith, the father of modern economics, warned against excessive borrowing to finance wars and unproductive expenditure. Yet he never opposed public investment that expanded national wealth and strengthened productive capacity.

 

John Maynard Keynes offered an entirely different perspective. During periods of recession, the central problem is not excessive public debt but insufficient demand and investment. If governments borrow to finance productive projects and employ idle labor, economic output rises, tax revenues increase, and the burden of debt may ultimately become smaller than it would have been had governments refrained from investing.

 

Joseph Stiglitz, Nobel Laureate in Economics, argues that discussions of public debt often begin with the wrong question. Instead of asking, “How much have we borrowed?”, policymakers should ask, “What have we invested in?” Spending on education, scientific research, infrastructure, clean energy, and healthcare should not be viewed merely as fiscal costs but as long-term investments that raise productivity and improve future living standards.

 

Mariana Mazzucato goes even further, arguing that governments are not merely market correctors but market creators. Public investment has played a decisive role in many of the world’s most transformative innovations, from the internet and GPS to advanced medical technologies. From this perspective, debt that finances innovation is not a burden but an investment in creating entirely new industries and markets.

 

Recent developments in macroeconomic thinking have reinforced this view. Olivier Blanchard has demonstrated that debt sustainability depends not only on the size of public debt but also on the relationship between the cost of borrowing and the rate of economic growth. When an economy grows faster than the interest rate paid on government debt, the debt burden becomes far more manageable, particularly when borrowing finances productive investments.

 

This reasoning has revived interest in an important fiscal principle known as the Golden Rule of Public Finance. Under this principle, governments may borrow to finance capital investment but should avoid borrowing to finance current expenditure.

 

The rule embodies an important concept of intergenerational fairness. Capital projects generate benefits for decades, making it reasonable for future generations that enjoy those benefits to share part of the financing burden. By contrast, borrowing to finance wages and day-to-day operating expenses merely shifts the cost of today’s consumption onto future generations that had no voice in the original decision.

 

International experience strongly supports this distinction. Following the Second World War, the United States, as well as South Korea, Singapore, and China, did not view public borrowing as either a virtue or a vice. Instead, they used debt strategically to finance infrastructure, education, energy systems, industrial development, and scientific research. These investments generated productivity gains and economic growth that ultimately exceeded the cost of borrowing itself.

 

Successful economies therefore do not simply distinguish between countries with high debt and those with low debt. They distinguish between debt that creates productive assets and debt that merely finances consumption. Accordingly, the appropriate measure of fiscal policy should not be the size of public debt alone but rather the quality of that debt, the economic and social returns it generates, and its contribution to productivity and national wealth.

 

Ultimately, future generations will inherit more than public liabilities. They will inherit the roads, ports, electricity grids, universities, hospitals, factories, digital infrastructure, and clean energy projects that today’s borrowing has made possible. If these assets generate income, employment, and sustained economic growth, public debt should be viewed not as a burden on the future but as an investment in it.

 

Conversely, when borrowing merely finances current consumption, it becomes exactly what Barro feared — a deferred tax imposed on generations that played no role in incurring it.

 

The question that should guide fiscal policy, therefore, is not “How much have we borrowed?” but “What have we built with that borrowing?” That is the question that ultimately determines whether public debt is a burden on future generations or a gift to them.

 

The writer is a former Jordanian minister of state for economic affairs