Markets have always been influenced by stories, but the speed, reach and impact of those stories now appear materially stronger. From historic episodes such as tulips and the South Sea Bubble to the dot.com boom and the current focus on artificial intelligence, narratives have often helped push asset prices beyond what fundamentals alone might justify. The difference today is that market stories can spread almost instantly, drawing in both retail and professional capital at a pace that can change risk conditions quickly.
The 2025 market environment showed how this can work in practice. Equity prices were shaped not only by earnings, balance sheets and valuation metrics, but also by acronyms, artificial intelligence themes and influential online figures. The so-called TACO trade reflected the view that tariff threats would soften when markets pushed back, encouraging buyers to step in during periods of weakness. At the same time, enthusiasm around artificial intelligence continued to influence valuations, while high-profile online personalities demonstrated how a single post could affect sentiment and capital flows.
Narratives can blur the line between perception and underlying value. When a story becomes dominant, recent price moves can be mistaken for evidence that the story is correct. Herding behaviour then reinforces the trend, as more participants follow what others are doing rather than making independent judgements. The result is a feedback loop in which rising prices support the narrative, and the narrative supports further buying.
Retail participation has added to this effect. Trading apps, zero-commission dealing and social media have made it easier for individuals to act quickly and collectively. Platforms that highlight popular stocks or sharp price moves can encourage short-term activity, while online communities can turn particular assets into cultural moments. This does not make retail participation negative, but it does mean that sentiment can now become a more powerful market force.
Fund managers also operate within stories, whether through company presentations, analyst meetings, conferences or benchmark pressure. When a dominant theme is driving an index or peer group, standing apart can carry career and performance risk. Even sceptical managers may feel pressure to maintain exposure to a prevailing narrative rather than move too early against it.
Market structure can further reinforce these waves. Systematic strategies and risk models often respond to volatility and price trends. When markets are calm, such models may permit greater exposure, helping an existing story continue. When volatility rises, the same mechanisms can force selling into weakness. Passive investing can have a similar reinforcing effect, as capital follows benchmark weightings that may have already been influenced by momentum.
In the early stage, a story may begin with a genuine fundamental basis that has not yet been fully recognised. This can create an attractive balance between potential upside and limited downside, particularly when an asset remains out of favour. Gold mining equities were cited as an example where rising bullion prices and improving margins were not immediately reflected in share prices, creating scope for the market narrative to catch up with fundamentals.
The second stage is more complex. Once a narrative becomes widely accepted, it can persist for longer than valuation discipline would suggest. Artificial intelligence is the obvious current example. The theme has substance, but high valuations, concentrated market leadership and questions about the return on large investment programmes all increase the importance of discipline around timing and exposure.
The final stage comes when prices move too far from fundamentals. At that point, the risk of reversal rises. Past examples, including meme stocks, technology shares and the dot.com period, show that a change in sentiment can be swift and material.
Ruffer Investment Company Limited (LON:RICA) is a British investment company dedicated to investments in internationally listed or quoted equities or equity related securities
