This post is part of our Battle of the Brands feature. Let us know which brand you prefer, and check out other Battle of the Brands posts.

To some degree, a face-off between Vanguard and Fidelity is really a face-off between John Bogle, Vanguard's founder, and Peter Lynch, Fidelity's star fund manager. While Bogle was a pioneer in no-load and low-cost investing in index funds, Lynch was a proponent of investing in "what you know," or getting investing ideas from your day-to-day life. BloggingStocks covered this Bogle vs. Lynch match up back in September, and readers gave the financial edge to Lynch.

Privately held Fidelity Investments is made up by two independent but closely cooperating companies: Boston-based Fidelity Management and Research LLC serves the North American market, and Fidelity International Limited (FIL), spun off in 1969, provides investment products and services to clients in the rest of the world. Fidelity reported revenue of $12.87 billion in 2006, by offering a large family of mutual funds, as well as providing discount brokerage services, retirement services, estate planning, wealth management, securities execution and clearance, life insurance, and a number of other financial services. The founding Johnson family still controls Fidelity, but Peter Lynch and some other fund managers also hold stakes in the company.

There are a handful or business commentators who are worth dropping everything and listening to, and I would put Vanguard Group founder John Bogle at the top of my list.

So that means everyone should drop everything and go read this interview he did with Fortune.

Always logical, some of Bogle's best wisdom comes on the topic of the bad mortgages that banks and hedge funds found themselves loading up on. Talking about his own experience making fixed income investments at Vanguard, he said this.:

The fixed income area is a stupid place to take risk. So, when someone came in and said, we can earn an extra half percent on this bond, I would say, do you think it has any higher risk? If not, why are they offering us an extra half percent?

It's absolutely fascinating that all these ostensibly intelligent people loaded up on subprime debt thinking that they could earn a higher yield without adding risk.

Forget complex reforms and more training -- maybe the executives who got their firms into this mess should have the graph above tattooed to their foreheads.

Check out the Bogle interview for his insight on other topics -- including his guess at the odds of a recession.