People would be a lot more skeptical if they understood that there is an incredible amount of chance in the results that you observe for active managers. So the distribution of outcomes is enormously wide - but that's exactly what you'd expect by chance with lots of active managers who hold imperfectly diversified portfolios. The really good portfolios contain a lot of really lucky picks, and the really bad portfolios contain a lot of really unlucky picks as well as some really bad ones.

People would be a lot more skeptical if they understood that there is an incredible amount of chance in the results that you observe for active managers. So the distribution of outcomes is enormously wide - but that's exactly what you'd expect by chance with lots of active managers who hold imperfectly diversified portfolios. The really good portfolios contain a lot of really lucky picks, and the really bad portfolios contain a lot of really unlucky picks as well as some really bad ones.

Markets are efficient, but there are different dimensions of risk and those lead to different dimensions of expected returns. That's what people should be concerned with in their investment decisions and not with whether they can pick stocks, pick winners and losers among the various managers delivering basically the same product.

The distribution of the market is fat-tailed relative to the normal distribution... For passive investors, none of this matters, beyond being aware that outlier returns are more common than would be expected if return distributions were normal.

An investor doesn’t have a prayer of picking a manager that can deliver true alpha.

I take the market-efficiency hypothesis to be the simple statement that security prices fully reflect all available information.

The efficient market theory is one of the better models in the sense that it can be taken as true for every purpose I can think of. For investment purposes, there are very few investors that shouldn't behave as if markets are totally efficient.