When we’re in our 80s, they say, a good part of our mental agility is going, going, gone.

That’s anything but the case with a couple of elder statesmen on Wall Street, however, both longtime publishers of well-regarded investment newsletters with strong followings. They’re Richard Russell, 82, and Charles Allman, 86, who between them have been doling out investment advice for 108 years.

I rang them up the other day and found both men up and about at their respective East and West Coast locations, articulate and perceptive, and sharply at odds on where the stock market is headed. One says up, though he has some near-term concerns, while the other says sideways to down.

Our bear, editor of the Growth Stock Outlook of Bethesda, Md., is Mr. Allman, who bases his negative case largely on his belief that the real estate collapse won’t end before 2010. His major concern here, he tells me, is the way more than $500 million in adjustable- rate mortgages will be reset at higher rates in 2008 and 2009. As aresult, hepredicts,”foreclosures will skyrocket and the economy will be clobbered.” As far as this year goes, he adds, “the news is there will be no housing comeback in the second half.”

Mr. Allman, who also manages $120 million of assets, believes Bear Stearns’s well-publicized hedge fund woes could be just the tip of the iceberg as far as the problems of the $2 trillion hedge fund industry go.

Yet another of his concerns is the mounting difficulties with radical Islam. “A clash of civilizations isn’t on the way, it has already started,” he said. At best, he believes, the market will travel sideways to slightly down for the balance of the year. More realistically, he says, “we could see a market correction of at least 10%.”

Mr. Allman’s advice to investors: “Put your chips on a dirty four-letter word spelled c-a-s-h.”

For those investors, though, who insist on stock ownership, he thinks the only sane strategy is a defensive one. In this context, he favors such names as Altria Group, Inc., GlaxoSmithKline PLC, Conoco Phillips, HSBC Bank, Chevron Corp., and Newmont Mining Corp.

Mr. Allman’s adversary, Mr. Russell, is a long-term bear and editor of Dow Theory Letters of La Jolla, Calif. But Mr. Russell turned bullish in May after seeing positive technical readings and a worldwide inflation boom combining to produce a more vibrant bull market than anyone expected. Byyear’send, hefigures the Dow — which closed Friday at 13,611 — could hit 15,000, about a 10% gain from current levels.

Higher inflation usually signals higher interest rates, a distinct negative for the economy and the stockmarket, but Mr. Russell contends the Federal Reserve Board, given the poor shape of housing, will be reluctant to boost rates.

Though a bull, Mr. Russell has reservations about the near-term direction of the market, largely because he thinks it’s overbought, a situation that could lead to a sideways correction. Among the worrisome signs he sees are a still deteriorating housing situation, the subprime mortgages mess, the rising price of oil, ongoing deficits, weakness in the dollar, and diversification out of the dollar by a number of countries. He also points to the parabolic increases in many of the world’s stock exchanges, not least the explosion in the Shanghai exchange.

The risk here is that an overvalued overseas market, like the Chinese market in February, could trigger a major decline here. The rampaging Chinese market tumbled 9%in a single day on February 27, which, in turn, sparked a wicked 416-point drop in the Dow.

Still, as our bull sees it, you have to differentiate between the near term and the longer term. The Dow, he said, would have to break its June 2007 low of 13,266.73 before the market could look potentially dangerous.

dandordan@aol.com