[pedrocr]

You can't diversify more than just holding the total market. And since market returns are zero sum for you to make that great profit someone else had to lose. I'll just take the market average at very low fees and not worry about it. That's what the first link explains.

[walshemj]

You can diversify across markets (different countries) and sectors and also to lay off risk, but I have been investing starting slowly with index funds 20 years ago so I think I have more experience.

I brought a commercial property fund when office prices crashed it tripled in less than 10 years.

[pedrocr]

>You can diversify across markets (different countries) and sectors and also to lay off risk

And you should. The ultimate goal is to own a cap weighted proportion of all the assets in the world. If you do anything other than that you're taking an active bet that some assets will do well and some poorly and someone else is taking the other side of that bet. The sharpe article is quite revealing.