In mid-December, Lucy Maurer, a Montgomery County delegate who has made a legislative career out of scrutinizing the complexities of public school finance, went to see House Speaker Benjamin L. Cardin to discuss what was later described as a philosophical issue of state education. In each hand, she carried a computer print-out, striped with columns of six-digit figures.

In one hand was the result of one plan Maurer's education funding subcommittee had devised for distributing state aid to the 24 counties and Baltimore City next year. Montgomery lost $1.4 million in funds. In the other hand was a second possible scheme, theoretically reflecting a different policy. Montgomery gained $700,000 over its current aid, and at the same time, Baltimore City and Prince George's County, the legislature's two most powerful delegations, gained nearly $500,000 each over the first plan.

Though the philosophical issue that separated the two schemes was real, it was so arcane that few people outside Maurer's subcommittee knew of its existence, much less understood it.And any policy difference that was actually reflected in the two formulas would have been almost impossible to detect amidst all the calculus -- much less argue with.

That, in large part, explains why Maurer stood at the door of Cardin's office with two sheets of dollar signs. And when, in the end, Maurer's subcommittee, on which Cardin sits, chose a plan, it was the figures, not the philosophy, that made it politically acceptable. The scheme favorable to Montgomery, Baltimore and Prince George's won.

In this way over the coming months of the legislature, debates will be built, issues will be grounded and policy will be set to the rhythm of perhaps the most powerful -- and sometimes least visible -- undercurrent in the General Assembly: numbers, or "data" as most legislators put it, and their myriad creative uses.

"Access to data equals power," is the way one skilled lobbyist here put it. And indeed, many of the most hotly-contested political disputes in the legislature, particularly in a year of sharp budget cutbacks, begin with wars of figures. While these dollar amounts and bodycounts often are accepted as symbols of objective reality in the everyday world, in the trenches of a state legislature they are quite frequently statements of political affiliation -- or propaganda.

In fact, in various contexts, "budget cuts" become accounting transfers, "aid cutbacks" become questionable projections, and even revenue estimates, the calculations of state tax collections that determine how much the state may spend each year, become halve-the-difference guesses when the mist clears from the numbers of Annapolis.

Last week, for example, as the House of Delegates sped through one of the short Monday night sessions that characterize the early weeks of the three-month session, a bill came up that sought to make emergency changes in a new state law that increases tax benefits for married couples.

Members of the leadership assured their colleagues that the bill represented simply a technical change of no substance, and when legislators checked the bill's "fiscal note" -- a document prepared by legislative staff for every piece of legislation that is supposed to show how much it might cost or save the state -- they found that the projected monetary impact of the law was supposed to be none.

In fact, though, while making only a technical change in a program passed last year, the bill the House quickly approved will cost the state $10 million in revenue this year by allowing the tax relief to go into effect.

So why did the leadership and staff say the bill would not cost anything?

Because, legislators said later, the money for the program already had been anticipated in the governor's budget -- and so, technically, the House was not doing anything new by agreeing to spend it.

And more to the point, several legislators noted, the House leadership did not want to revoke tax relief that had been approved last year. By not emphasizing that fat $10 million figure, they left little opportunity for the fund-starved legislature to reconsider what it did in a year of abundant resources.

Members of the leadership are not the only ones adept at the numbers game. When Gov. Harry Hughes released his first proposed state budget to the legislature in 1979, he said it contained the smallest increase in state spending since 1962. Last year, his aides made the same claim when the governor's second budget was submitted.

Although he was correct at the time, in fact neither budget turned out to have the same low increase in spending by the time it was approved. By the time Hughes finished submitting supplemental appropriations, the rate of spending growth rose from 7.7 percent in 1979 to nearly 11 percent; and from 6.7 percent in 1980 to over 12 percent. These rates were about the same as in the few years before Hughes took office.

This year, in detailing his third budget, Hughes' submittal message says, "these growth rates are the smallest since the initial budget for fiscal 1962." "

"Well, we're in a different situation this year," says Hughes press secretary Gene Oishi, explaining that the state's estimated revenues are not likely to rise in the next two months as they did in past years, allowing increases in the budget.

Legislative fiscal staffers agree this is true, but it is nevertheless in the state budget that numbers frequently don't always mean what they appear to.

There were, for example, the "3 percent cuts . . . and other actions" that the governor announced he was planning to make in state programs last September to "produce an estimated savings of $50 million." In early December, Hughes announced that he had met his goal, but when he released his list of the $52 million in savings, $35 million of it turned out to be "reversions" -- funds that had been appropriated to agencies but turned out not to be needed.

In addition, of this $35 million, which should have shown up even if there had been no spending reduction plan, some $15 million had been anticipated, and reported, at the time Hughes announced his reduction program. aAnd so, although the governor's statements were officially correct, he really found only $35 million between September and December of the $52 million and cut only $17 million -- or an average of 1.8 percent -- from agency programs.

And in some cases, items that were reported as "cuts" by state departments to meet the genuine problem of shrinking state revenues were not really cuts at all. In the Department of Human Resources, for example, department officials under pressure to make cuts decided to take $4 million in federal funds that normally would be accepted next year and put them in this year's budget.

The officials then used the extra $4 million in federal funds to reduce state funds by a like amount, and reported the change as one of their cuts to the state budget department, even though there was no reduction in spending involved at all, according to budget department staff. Meanwhile, in 1987, the human resources administrators plan to have a few million extra in state funds for their program, to pay back for this year's maneuver.

Then there are cases where phantom money appears in the state budget. In the current budget for the year ending June 30, the state Department of Transportation lists $10 million in income from the Maryland Transportation Authority, which operates state toll facilities.

The money represents revenue from state highway and bridge toll booths that is not needed to keep the bridges and toll roads open. State officials estimated there would be $10 million left over, and that the authority would give it to the state for other transportation projects. But though the right amount of money has accumulated, several of the board members now think it should be kept in reserve for a future Baltimore tunnel project.

And so the Department of Transportaion, already under fire from the legislature for cutting back on funding for new roads and maintenance work, may now have to tell its adversaries that $10 million on its financial statements effectively doesn't exist.

For every package of numbers in state government, there is usually one expert; and every political faction has its own mathematical wizards to churn out its facts and bolster its arguments.

In the case of revenue estimates -- perhaps the most important of the millions of figures circulating in state offices -- the technician is Robert D. Rader, a tall, blond economist from West Virginia who for the past seven years has been compiling the figures that determine how much the state can spend each year.

Rader, working for months at a time on the official estimates reportedf two or three times a year, uses four different methods to predict how much will be collected through the state sales tax, the state income tax, the property tax and other sources, and he tries to guess exact dollar figures almost two years before the money will be counted.

Once he arrives at a set of figures, Rader sends it on to the Board of Revenue Estimates, which includes the state treasurer, state comptroller and state budget director. This group is shrouded in an aura of Delphic mystery as it decides on figures that can mean expansion or death for various state services.

But the history of one revenue estimate shows how in the chancey world of prediction, despite computer programs, sophisticated financial trend reports and decades of experience, the selection of revenue estimates can become relatively unsophisticated at times.

In October 1979, Rader's techniques produced estimates for retail sales tax collections for the year ending this June that ranged from a computer's projection of $764 million to an economic analysis technique that yielded $775 million. Rader eventually decided to fall in between and recommended a figure of $770 million to the board.

But Treasurer William James, Budget Director Thomas Schmidt and Comptroller Louis Goldstein, citing their perception of worsening economic figures, decided to lower the figure to $760 million -- $15 million less than Rader's highest figure -- and that was the estimate Hughes used when he started writing the budget now in effect.

"Sometimes," Rader explained, "it's hard to be too sophisticated. You just have to go on judgment."

And, it appears now, if $18 million worth of sales tax exemptions passed by the legislature last year is discounted, the original, computer-processed high estimate of $774 million is closest to being right.