Post-Keynesian economics is a school of thought that builds on the most radical ideas in John Maynard Keynes's General Theory (1936): that the future is genuinely uncertain, that spending drives output and employment, and that a money-using economy can stay stuck in unemployment or slide into crisis on its own.
It's one of the largest and most influential heterodox economics traditions, and after the 2008 financial crisis it gained a much wider audience. Here's what it says, in plain English.
Where Post-Keynesian Economics Comes From
After Keynes died in 1946, mainstream economists folded his ideas into what became known as the "neoclassical synthesis," keeping the policy conclusions but dropping much of the deeper theory. A group of economists, many of them at Cambridge, argued that this lost what was most important. They included:
- Joan Robinson, who pressed the case that economies move through historical time, not toward a timeless equilibrium
- Michał Kalecki, who independently developed a theory of effective demand, grounded in how firms set prices and how profits depend on investment
- Nicholas Kaldor, who studied growth, manufacturing, and endogenous money
- Hyman Minsky, the American economist whose theory of financial instability is now famous
The Core Ideas
1. Fundamental uncertainty
Mainstream models usually treat the future as risky but calculable: you may not know what will happen, but you know the odds. Post-Keynesians follow Keynes in arguing that for many important decisions, such as building a factory or lending for 30 years, the odds simply can't be known. People fall back on conventions, rules of thumb, and confidence, what Keynes called "animal spirits." That makes investment volatile and the economy prone to swings.
2. Effective demand
In the Post-Keynesian view, spending determines output, in the short run and the long run. If households, firms, and government don't spend enough, firms don't produce, and people stay unemployed, even if they'd happily work for lower wages. Cutting wages can make things worse, because workers are also customers.
3. Endogenous money
Textbooks often describe banks as lending out deposits that savers bring in. Post-Keynesians argue the reverse: banks create new money when they make loans, and the central bank sets the interest rate rather than the quantity of money. In 2014, the Bank of England published an article, "Money creation in the modern economy," explaining that this is how money creation works in practice.
4. Distribution matters
Who gets income matters for how much gets spent. Workers tend to spend more of their income than the wealthy, so rising inequality can drag on demand, a theme in Post-Keynesian work on wage-led growth.
Minsky's Financial Instability Hypothesis
Hyman Minsky's big idea was that stability is destabilizing. During good times, borrowers and lenders grow confident, and finance moves through three stages:
- Hedge finance: borrowers can repay both interest and principal from their income.
- Speculative finance: borrowers can pay the interest but must roll over the principal.
- Ponzi finance: borrowers can't even pay the interest and rely on rising asset prices to stay afloat.
When asset prices stop rising, Ponzi borrowers are forced to sell, prices fall, and the whole system can unravel. The term "Minsky moment," coined by the investor Paul McCulley in 1998, describes the moment the music stops. When the subprime mortgage market collapsed in 2007–08, Minsky's long-neglected work suddenly appeared in newspapers and central bank speeches.
What Post-Keynesians Recommend
Post-Keynesians differ on details, but many favor:
- Active fiscal policy to keep demand near full employment
- Strong financial regulation, because markets don't police their own risk-taking
- Policies that support wages and reduce inequality
- Low interest rates set by the central bank, with fiscal policy doing more of the work
Modern Monetary Theory grew out of Post-Keynesian thinking about money and government finance, extending the tradition in some directions and departing from it in others.
Common Criticisms
Mainstream economists argue that Post-Keynesian models are less precise, harder to test, and that modern New Keynesian models already include demand shortfalls and financial frictions. Some also argue that Post-Keynesians underrate the risk of inflation from sustained deficits. Post-Keynesians respond that modern mainstream models were added on after 2008 and still treat crises as external shocks rather than something the system produces itself. Weighing those arguments yourself is the best way to understand both sides.
How to Study Post-Keynesian Economics
A good reading path is Keynes's General Theory (chapters 12 and 17 especially), Minsky's Stabilizing an Unstable Economy, and Marc Lavoie's Post-Keynesian Economics: New Foundations for a modern overview. Few universities teach Post-Keynesian economics in depth.
Elton University's Post-Keynesian and heterodox economics master's lets you study Post-Keynesian theory 1-on-1 with professors who know the tradition from the inside, alongside mainstream macroeconomics and any other school you choose. You can apply it to the questions you care about, from financial crises to housing to climate finance, and build a portfolio of research and policy work along the way.
Interested in studying Keynes, Minsky, and the economics of uncertainty? Talk to an admissions officer or explore Elton's economics program. Elton University is a 501(c)(3) nonprofit university — EIN 86-2426898.
Sources
- Keynes, J. M. (1936). The General Theory of Employment, Interest and Money. Macmillan.
- Minsky, H. P. (1986). Stabilizing an Unstable Economy. Yale University Press.
- McLeay, M., Radia, A., & Thomas, R. (2014). Money creation in the modern economy. Bank of England Quarterly Bulletin, Q1.
- Lavoie, M. (2014). Post-Keynesian Economics: New Foundations. Edward Elgar.