According to Robeyns, a crucial part of the solution lies in the hands of investors and financial institutions, who have the power to shape economic structures and curb excessive wealth accumulation. For our podcast series Inside Impact Investing, Robeyns discusses her book, Limitarianism: The Case Against Extreme Wealth with Triodos’ Chief Economist Hans Stegeman. In the conversation, she outlines why wealth concentration is a significant moral and economic issue, and how investors can take active steps to prevent it.

The morality of extreme wealth

Robeyns emphasises that the world is facing multiple crises, particularly ecological degradation and rising socio-economic inequality. “We just know from history that if you have big structural challenges, you need activists to change something,” she states, highlighting the importance of those who fight for systemic change.

Limitarianism, as she describes it, is the symmetrical opposite of a world without poverty. Instead of merely seeking to eliminate extreme poverty, it advocates for a society where excessive personal wealth is deemed unnecessary and even harmful. “Limitarianism assumes that this world is a better world,” she explains. “And also, that it’s the only just world because extreme wealth concentration is, according to my analysis, unjustified.”

The societal costs of wealth accumulation

The problem with extreme wealth, Robeyns argues, is not just about fairness but also about its corrupting influence on society. Excessive wealth provides individuals with disproportionate power, allowing them to shape policies, influence political decisions and monopolise resources. “It also corrupts society in the end,” she says. “The idea that we could accumulate capital or private property endlessly - we just think this is normal. And the fact that most people do think so suggests that this is the dominant idea.”

Moreover, extreme wealth is often amassed through dubious means. In her book, Robeyns discusses the concept of “dirty money”, arguing that a significant portion of wealth stems from unethical practices such as tax evasion, monopolistic business models, and historical injustices. “If the money you have is tainted with the blood from labor from enslaved people, that’s almost as bad as it can get,” she asserts, citing examples of wealth derived from colonial exploitation.

The role of investors and the financial sector

A key argument against extreme wealth is that it often results from privilege and luck rather than merit. Robeyns challenges the neoliberal notion that success is purely the result of individual effort. “Being lucky, I think, is really an enormous factor in our lives that we tend to deny,” she notes. Many of today’s billionaires gained their wealth through market dominance, inherited assets, or fortunate investments - factors that do not necessarily reflect personal merit.

The financial sector, she argues, plays a crucial role in perpetuating this cycle. “The financial sector serves the rich much better than poor people,” she states. “Rich people get their own private banker to make sure they retain their wealth or even get more wealthy.” As a result, the system continues to favour those at the top, exacerbating inequality.

Investors have a moral responsibility to ensure their capital does not contribute to extreme wealth accumulation. Ethical investment strategies, such as prioritising companies with fair executive pay policies and refusing to fund exploitative industries, can play a key role in limiting excessive wealth. As Hans Stegeman notes, “Triodos Investment Management always looks at the CEO pay when investing in listed companies. If it’s too high, we exclude those companies.” He acknowledges that this approach can come with trade-offs. “Sometimes it hurts your own business model, but I think that’s also a question of morality within the financial sector, to ask ourselves: we can do it, but should we do it?”

A limit to wealth

One of the most provocative aspects of Robeyns’ argument is the idea of a wealth cap. In her research, she has explored what an appropriate “richest line” might be, using empirical studies from the Netherlands and the UK. “Although people disagree on where to put the limit, almost everybody agrees: yes, there is a limit,” she explains.

In her book, she suggests that EUR 10 million should be the upper limit for personal wealth. “I would have preferred not to give a number,” she admits, “but then people might have said: I agree about a limit, let’s put it at 1 billion.” She stresses that this figure is not absolute but a starting point for discussion. “I also just think that there’s a moral limit... what should you as an individual think you should keep? And I think the upper limit should be EUR 1 million.”

Political and economic feasibility

The main challenge with implementing limitarian policies is the global mobility of capital - the ability of the wealthy to move their assets to low-tax jurisdictions. Robeyns believes that countries should take bold steps to address this. “A tax report that came out recently showed that new legislation requiring a minimum 15% tax is already leading to all kinds of attempts to find loopholes,” she warns. “If we don’t tackle the heart of the problem, this is just going to continue.”

Possible solutions include higher inheritance taxes, wealth taxes, and international cooperation to eliminate tax havens. “We need much more capacity to check tax returns and deal with fraud,” she argues. “It is mind-blowing that we have given up on the possibility to democratically regulate and control what the richest people in the world do.”

Moving towards a more just society

Robeyns concludes that limitarianism is not about punishing the rich but about ensuring a fairer distribution of resources. “We should weigh all the different interests and try not to get into a position where we have to maximise profit-seeking,” she insists. She cites Patagonia founder Yvon Chouinard, who structured his company to prioritise ethical considerations over shareholder profits, as an example of responsible wealth management.

Ultimately, Robeyns urges society to question the assumption that limitless wealth is acceptable. “The nastiness of this problem is that a lot of it is international,” she acknowledges. “But that is not an excuse to do nothing.” Whether through taxation, corporate responsibility, ethical investment choices, or financial regulation, she argues that the time to challenge extreme wealth is now.

Listen to the podcast with Ingrid Robeyns and Hans Stegeman.