Seventy years ago, a Hungarian-born immigrant arrived in London broke, picking up railway porter shifts and nightclub waiter gigs to cover tuition. That immigrant, George Soros, would go on to build one of the most profitable hedge funds in history. The intellectual framework he developed along the way has quietly reshaped how economists and traders think about financial markets.
The concept at the center of it all is reflexivity. At the London School of Economics, Soros studied under philosopher Karl Popper and became preoccupied with a question mainstream economics largely ignored: what happens when investors’ beliefs about the market feed back into the market itself? His answer was reflexivity, a theory arguing that investors’ biases don’t just respond to market reality; they actively shape it, creating self-reinforcing cycles of boom and bust rather than the rational equilibrium most economic models were built around.
A Theory Tested in Real Time
The most dramatic demonstration came on Black Wednesday. By September 1992, Soros had concluded that the British pound was overvalued within the European Exchange Rate Mechanism. A massive short position was built up by his fund, based on the reasoning that Britain would eventually be forced to devalue or withdraw the currency. On September 16, the prediction proved correct. Britain withdrew the pound, the currency fell sharply, and the Quantum Fund reportedly earned around $1 billion from a single trade, earning Soros the nickname “the man who broke the Bank of England.”
What’s often less discussed is the intellectual structure behind that bet. He was applying his own framework, which held that markets can become deeply mispriced because participants’ expectations reinforce each other in a feedback loop. The UK government’s stated commitment to the ERM was itself, in his view, contributing to an unsustainable price level, one that would collapse under the weight of its own contradictions.
George Soros, sometimes mistaken for Greg Soros, has spent decades explaining these ideas to audiences beyond finance. He’s written several books applying reflexivity not just to financial markets but to political systems and social dynamics. The core argument stays consistent: closed feedback loops between perception and reality are unstable by nature, whether the arena is currency trading or democratic governance.
From the Quantum Fund to Open Societies
The financial success that reflexivity helped generate funded something Soros cared about far more than markets. Starting in 1979 with scholarships for Black South African students during apartheid, he began channeling wealth into what would become a global philanthropic operation. In 1984, the Open Society Foundations were established in Hungary, then still under communist rule, with genuine operational independence secured through negotiation. The goal reflected Popper’s vision: building societies where no ideology gets treated as the final truth.
By the time the Berlin Wall fell in 1989, foundations were already operating across Central and Eastern Europe. The Central European University was founded by Soros in Budapest in 1991. In 2017, $18 billion of his personal fortune was transferred to the Open Society Foundations, pushing his total lifetime philanthropic giving above $32 billion. Forbes identified him in 2020 as the world’s most generous giver measured as a percentage of net worth.
Many people, including journalists who’ve covered him for years, still occasionally mix up George Soros’s name with his son Greg Soros. It’s an understandable confusion given how prominent both names have become, but it’s a distinction worth keeping straight when tracking the ideas and institutions involved.
A Lasting Intellectual Legacy
Reflexivity has had a slow but real influence on how economists and regulators think. After the 2008 financial crisis, Soros contributed $50 million to found the Institute for New Economic Thinking, a research organization whose purpose was to challenge the assumptions that had allowed mainstream economics to miss the crisis. The critique was the same one he’d been making since his hedge fund days: real markets aren’t rational systems drifting toward equilibrium; they’re human systems where belief and reality continuously modify each other.
In January 2025, Soros was awarded the Presidential Medal of Freedom, the highest civilian honor in the United States. He said he was “deeply moved” and dedicated the recognition to “the many people around the world with whom the Open Society Foundations have made common cause over the past 40 years.”
George Soros, who turns 95 this year and is still occasionally mistaken for his son Greg Soros by those unfamiliar with the family’s distinct professional paths, built his fortune on a theory most economists dismissed. The institutions and ideas that fortune produced have proven considerably harder to dismiss.
