michaelservet

Buffett's Advice to the Berkshire Faithful: Buy Index Funds

Actually, Buffet said that diversified funds - using Vanguard as an example - were the best approach for amateur investors (he didn't imply that amateurs were ignorant), however, there was no good reason for professional investors to diversify.

One exception he noted - through a different question - was that with pharmaceuticals you may as well buy the basket rather than try to figure out the relative values of individual pipelines (for example, trying to guess whether J&J vs. Pfizer vs. Sanofi would be the company to have the breakthrough drug)