On a crisp morning stroll through Edinburgh recently, whilst following my son’s rugby team in the UK, I found myself at the Scottish National Gallery of Modern Art, where Eduardo Paolozzi’s 1989 statue of Sir Isaac Newton caught my eye. Cast in bronze with geometric fragments, Newton is depicted as the “Master of the Universe,” his head bowed intently over mathematical instruments. It’s a mesmerising tribute to one of history’s greatest intellects, immortalised in deep contemplation of the cosmos.

But statues don’t tell the full story. What Paolozzi’s work omits is Newton’s humiliating financial debacle during the South Sea Bubble of 1720-a cautionary tale that resonates profoundly in today’s volatile markets. Historical accounts reveal that Newton initially invested a modest sum in South Sea Company stock, cashed out with a respectable profit, then watched enviously as his friends amassed fortunes while prices skyrocketed. Succumbing to the fear of missing out (FOMO), he re-entered the market near its peak with a much larger stake [1]. When the bubble inevitably burst, Newton lost approximately £ 20,000, equivalent to about £6 million today (adjusted for inflation), or roughly $14 million in New Zealand dollars [2]. His wry reflection afterwards? “I can calculate the motions of heavenly bodies, but not the madness of people” [3].

This episode isn’t just an amusing footnote in the life of a scientific giant; it’s a stark reminder that even the sharpest minds are vulnerable to market mania. If Newton, the architect of calculus and gravity, couldn’t outsmart the crowd, what hope do everyday investors have in navigating today’s hype-driven landscapes, like the AI boom?

Unpacking the Bubble Phenomenon

Financial bubbles are seductive traps, identifiable only after they’ve popped. They thrive on compelling narratives that mask underlying risks. In 1720, the South Sea Company’s promise of exclusive trade rights with South America fuelled wild speculation, driving stock prices from around £100 to over £1,000 in months before collapsing [4]. Closer to home, New Zealand’s 1987 sharemarket crash serves as a vivid parallel: fuelled by deregulation and easy credit, the NZSE index surged, only to plummet 60% in weeks, wiping out leveraged fortunes in property and equities [5, 11]. The aftermath was brutal: bankruptcies, shattered families, and a lingering distrust of markets that scarred a generation.

More recently, Auckland’s property market exhibited bubble characteristics, with median house prices tripling between 2011 and 2021 amid low interest rates and high demand [6]. These episodes highlight a pattern: euphoria driven by “this time it’s different” optimism, followed by inevitable reversion to fundamentals.

Enter today’s hottest debate: artificial intelligence. Is AI the next fire, wheel, or microchip-a paradigm shift revolutionising healthcare, agriculture, and beyond? Or is it overhyped, with valuations echoing the dotcom bubble, where slapping “.com” on a business sent stocks soaring regardless of viability [7]? Companies like Nvidia have seen shares rocket over 100% in the past year on AI enthusiasm, but sceptics warn of irrational exuberance. The truth? No one knows for sure. AI could deliver transformative value, or it might follow the path of past tech fads, leaving late entrants holding the bag.

Why Diversification is Your Best Defence

In the face of such uncertainty, diversification emerges not as a conservative cop-out, but as a strategic imperative. When predicting individual winners is near-impossible, the smart play is to spread your bets across the market. Own a broad index fund, and let capitalism’s machinery-competition, innovation, and resource allocation-work its magic over the long haul.

Strolling Edinburgh’s Royal Mile, I paused at the statue of Adam Smith, the Scottish economist whose 1776 masterpiece, The Wealth of Nations, introduced the “invisible hand” [8]. Smith argued that self-interested individuals, through free markets, inadvertently create societal benefits by directing capital to its most productive uses. No top-down planning required-just the aggregate wisdom of millions of decisions fostering efficiency and growth.

This evolutionary aspect of capitalism is key: viable companies flourish, while hype-driven ones wither. Yet spotting them in advance is a fool’s errand. Studies show that even seasoned fund managers underperform broad market indices over time, with survivorship bias and fees eroding returns [9]. For individual investors chasing the next Amazon or dodging the next Enron, the odds are stacked even higher against success.

New Zealanders have ample tools for diversification: local or global index funds covering thousands of companies, often accessible via platforms like KiwiSaver. These vehicles ensure you participate in growth sectors like AI without overexposure. Miss the ground-floor entry on Nvidia? No problem-a diversified portfolio still captures the upside while shielding you from sector-specific crashes.

The Psychology of Smart People Making Dumb Moves

Newton’s misadventure underscores a timeless truth: raw intelligence offers no immunity to behavioural biases. As Daniel Kahneman explains in Thinking, Fast and Slow, our brains are wired for quick, intuitive decisions that often lead us astray in complex environments [10]. Newton fell victim to a classic cycle: initial caution (fear of loss), sidelined envy (FOMO), and impulsive greed fuelled by social proof from his peers.

This dynamic played out vividly in New Zealand’s 1987 crash. Professionals-doctors, lawyers, accountants-piled into “can’t-lose” investments with borrowed money, convinced by the herd that prices would rise forever. When reality hit, the rapid 60% drop erased wealth overnight, triggering a cascade of personal and economic fallout [11].

Human nature hasn’t evolved since Newton’s day. Greed, fear, and herd mentality persist, amplified by social media and 24/7 news cycles. In the AI era, viral success stories can lure even savvy investors into concentrated bets, ignoring the risks.

Building Resilience Through Diversification

While diversification won’t eliminate downturns (markets are volatile by nature), it mitigates ruinous losses. Imagine holding only South Sea stock: total devastation. But a basket of British equities? Painful, but survivable, with recovery potential. The MSCI World Index’s ~8% average annual gross return over 30 years, weathering multiple crashes, exemplifies this resilience [9].

Apply this to AI: if it revolutionises society, diversified holders benefit via broad tech exposure. If it fizzles, your portfolio’s other sectors (healthcare, consumer goods, energy) provide ballast [12]. The key is discipline: resist the siren call of hot tips and maintain a balanced allocation.

Final Reflections: Wisdom from the Past

Gazing at Newton’s statue, the irony hit me: a monument to unparalleled genius, yet its subject was felled by the same primal instincts that plague us all. Bubbles will recur because human psychology is immutable. But we can arm ourselves with humility, acknowledging our limitations in outguessing markets.

Embrace diversification as your anchor, harnessing capitalism’s long-term compounding power. You don’t need Newton-level brilliance to thrive financially-often, recognising your non-genius status is the cleverest strategy.

And don’t go it alone. Newton might have avoided disaster with impartial advice. A trusted financial adviser won’t forecast the next bubble but will enforce discipline: reminding you that past performance doesn’t predict future results, crowds are often wrong, and capital preservation trumps speculative gains. They’ll tailor a diversified plan to your goals, helping you navigate emotional turbulence and emerge stronger.

In an unpredictable world, this approach turns potential pitfalls into opportunities. Review your portfolio today: is it diversified enough to withstand the next mania? If not, seek wise counsel-it could be the difference between exiting happy and exiting broke.

**Nick Stewart**
*(Ngāi Tahu, Ngāti Huirapa, Ngāti Māmoe, Ngāti Waitaha)*
Financial Adviser and CEO at Stewart Group

Stewart Group is a Hawke's Bay and Wellington based CEFEX & BCorp certified financial planning and advisory firm providing personal fiduciary services, Wealth Management, Risk Insurance & KiwiSaver scheme solutions.
The information provided, or any opinions expressed in this article, are of a general nature only and should not be construed or relied on as a recommendation to invest in a financial product or class of financial products. You should seek financial advice specific to your circumstances from a Financial Adviser before making any financial decisions. A disclosure statement can be obtained free of charge by calling 0800 878 961 or visit our website, www.stewartgroup.co.nz
Article no. 428

References

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