LONDON  The central question dividing economists these days is whether Western governments should spend more to ward off a potential second recession or retrench to hold down their ballooning debts to restore confidence among investors.

But Albert Edwards, an investment strategist in London for the French bank Société Générale, considers the debate a waste of time. To be specific, he forecasts a “bloody, deep recession” that produces a stock market collapse of at least 60 percent, followed by years of inflation of 20 percent to 30 percent as the persistent printing of money by central banks desperate to improve the situation sends prices soaring.

Mr. Edwards’s sandals and chuckling demeanor belie his reputation as perhaps the City of London’s best-known permabear  a species that has long flourished on the outer margins of the financial industry but rarely inside mainstream banks.

That is no longer true.

With the shocking financial crisis of 2008 still fresh in people’s minds, and gloom-spinning economists like Nouriel Roubini having achieved pop culture status, even longstanding pessimists like Mr. Edwards  who has been forecasting a Japanese-style stock market slump in the United States since 1997  are being treated with newfound respect.