Warren Buffett has long stressed the importance of independent research in investing. While markets are filled with opinions, forecasts, and hype, Buffett warns that relying too heavily on others can be costly.
“The key to investing is not how much you know,” Buffett has noted, “but how realistically you define what you don’t know.” His approach underscores the value of careful research, analysis, discipline, and sticking to businesses you understand.
That same discipline guided him into major investments in Japan. At the 2025 Berkshire Hathaway Annual Meeting, Buffett recalled starting with a handbook—filled with listing companies two to a page. “It’s amazing what you can find when you just turn the page,” he said. “Turning every page is one important ingredient to bring to the investment field. Very few people do it—and those who do aren’t going to tell you what they’re finding.”
By doing your own research, Buffett argues, you avoid being swept up in speculation and gain the confidence to hold investments through volatility. In his view, sound decisions come not from chasing trends but from clear-eyed judgment about a company’s ability to generate long-term value.
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© 2025 David Mazor
Disclosure: David Mazor is a freelance writer focusing on Berkshire Hathaway. The author is long in Berkshire Hathaway, and this article is not a recommendation on whether to buy or sell the stock. The information contained in this article should not be construed as personalized or individualized investment advice. Past performance is no guarantee of future results.