Some cruel stepmother must force all apprentice pollsters to memorize the first rule of political polling--that combination mantra and disclaimer of their profession. If you ask any pollster, anytime, if the survey numbers indicate sure victory or defeat next Tuesday, you will get the same response everytime: "Any poll is only a snapshot of the electorate at a given point in time. No poll can accurately predict what will happen in the future." Sorry.

But the pollsters' protective code was recently breached by the respected and circumspect Peter Hart. At the risk of some ego and professional pride, Hart offered a detailed diagnosis of the American body politic and a prognosis for the 1982 election campaign. Here is where we are politically and where we will probably be going, according to the Hart line.

The Moral Majority. Right now, the Rev. Jerry Falwell enjoys positive support among American voters practically identical to that accorded to former president Richard Nixon--about one week before he resigned his office. About one-fourth of the electorate takes kindly to the Falwell cause. The rest of the folks are, at best, indifferent and frequently openly hostile--to the legislative agenda of the Moral Majority. Hostility is especially prevalent among the huge under-40 generation of voters. Those are the voters who will essentially determine whether the much-advertised realignment of our national politics actually does occur in either 1982 or 1984.

Obviously, the recent failures of the Democrats on the central issues of inflation and the economy have provided the Republicans with a historic opportunity. That opportunity--to appeal to and win younger voters-- could be squandered by Republicans who insist "on playing the short-side of the political field on the 'life style-social' issues." Virtually every poll shows that the under-40s are downright "laissez-faire" on the question of what other people do in private, that is, their life styles. A Falwell-GOP alliance in 1982 would almost surely spell disaster for the Republicans.

Public Dialogue of the 1982 Campaign. It has yet to be set. There is no guarantee that the economy, or the president's program to right it, will be at the top of the national agenda in the fall of 1982. Hart does believe that the intensely negative and viciously personal campaigns that blighted the politics of 1980 may be on the way out. He points out that such negative tactics boomeranged this year in both Los Angeles and San Antonio. Like all good pols, he knows that our campaigns are highly imitative. How many candidates have you seen striding toward the camera with shirt collar unbuttoned and suit jacket over the shoulder? If word gets around that negative campaigns are not working, we will see fewer negative campaigns.

Here, according to Peter Hart, is how to tell who's ahead in the 1982 campaign. If, anytime between now and Halloween of next year, you hear the Republicans trying to pin blame for our economic plight on previous Democratic administrations, then the GOP is in big trouble. Voters, who are pretty discerning people, know that the president got everything he wanted, and even a little extra, in his economic program. Voters know that the Reagan policies are getting a full and fair tryout.

There are a couple of emerging Democratic beachheads in the 1982 campaign. In addition to the environmental debate, where voters are suspicious of Republican pro-industry sympathies, there appears to be a growing perception that the Reagan policies intentionally and deliberately favor the wealthy and the powerful over working families. On Social Security, the Republicans are saddled with the image of being uncaring and insensitive about the fate of older people. That can only be a liability for 1982.

The unifying Democratic theme for 1982. There isn't one. The Democrats now find themselves without a public vision to offer to the voters, or so much as a rallying cry with which to recruit 1982 candidates for federal office. Not being a Republican and being for Social Security do not add up to a reason for enduring all the costs of running for Congress.

After 17 years in the political battles, Hart remains the passionate professional. Before he will contract out his talent and his energy to any candidate, he insists that the candidate first answer one question: What does the candidate want written on his or her political tombstone? Come to think of it, that's a pretty good question to ask of all candidates in 1982. It's one that neither party is prepared to answer in the summer of 1981.