Bond guru Bill Gross has benefited from U.S. monetary policy for the last 30 years and is unaware that the environment that made him successful has radically changed, a fund manager told CNBC on Thursday.
"It's a Volcker career," Michael Browne, from the U.K.-based investment firm Martin Currie, told CNBC. He referenced the policies of Paul Volcker, the former chairman of the Federal Reserve, who in the early 1980s aided a long-term rally in fixed income assets.
Browne was reacting to comments made by Gross on Wednesday in an interview with CNBC.
Gross, who now works for Janus Capital after managing the world's biggest bond mutual fund at Pimco, said he was concerned about liquidity drying up in the next few years, with central banks looking to raise benchmark interest rates.
"You would think that a central banker wouldn't stop if they knew that it would produce a crisis type of moment, and lots of volatility, but central bankers don't exactly know the way home and so we'll just have to see," Gross said in an interview with CNBC's "Power Lunch."
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Browne responded by saying that it was Gross himself who didn't know how to "find his way home."
He argued that an "earthquake" had destroyed the world in which Gross had operated before the global financial meltdown of 2008, and called the bond expert's work: "nice, neat monetarist economics."
"We must be in a new world," Browne said, noting that fixed income assets and equities no longer had the correlation they experienced before the financial crash.
For decades, stocks and bonds tended to move in opposite directions, but in the late 1990s they had developed a positive correlation. After months of volatility, analysts are now contemplating what their new relationship could be, with bonds prices falling on increased inflation expectations.
"We need to think again and we need to start again. We need to have a completely different set of rules," Browne stressed. "The world… has moved to a different monetary paradigm."
If fixed income and stocks continue to be inversely correlated, Browne said the financial system would have to adapt to that new environment, which would mark a very different period of economic development.
Gross did not immediately respond to a CNBC request for comment.