The founder of a $3.9 trillion investment giant has some advice for wannabe money managers

Index funds are eating into the field of traditional money management, hurting prospects for would-be stock pickers.

But that doesn't mean all is lost for young people seeking Wall Street careers, says John Bogle, the father of index investing at $3.9 trillion Vanguard.

In an extensive interview with Business Insider, Bogle advised young people to "follow their star," pay little heed to previous generations and to make the money management business better.

Here's Bogle's full quote (emphasis added):

"I would always advise young people to follow their star, not my star. They have to live their own life. If they decide they want to go into the investment business, do it but make it a better business than it is today.

I think high turnover is definitively the investor's enemy, so you don't want to bring a high turnover philosophy to this business. You want to have a long term philosophy.

The business has some problems, substantial problems. You go fix it, you young people. That's what you're there for. Don't believe what the old generation tells you. We don't know a damn thing, including Bogle."

Vanguard has taken the lead in cutting fees compared to Wall Street's active money managers, eating into their profits as investors shift their assets into the cheaper index funds.

You can read Business Insider's full interview with Bogle here.