IN RECENT WEEKS people as diverse as Vernon Jordan, Griffin Bell, Jerry Brown, Sen. Paul Tsongas and the Rev. Theodore Hesburgh have advanced the notion of national service, and a bipartisan group of congressmen has joined Pete McCloskey in introducing a national service bill.

On past occasions the same banner was carried by John Connally, Argent Shriver, Robert NcNamara, Andrew Yound, Lyndon Johnson -- and William James.

In the Feb. 25 Outlook, William Greider attacked national service as a "vicious,... rotten idea" being pressed "by an obscene coalition between the liberal establishment and the right-wing militarists." He commended the "informed cynicisn" of young people who "have seen with clear eyes an adult world whose government indulged murder, bribery, lying, pointless war," and asked why his children should be coerced into national service and thus punished for the sins of their fathers.

Cynicism may indeed be a long-lasting legacy of Vietnam and Watergate. Still, shouldn't we hope that our children will now move on to a healtheir skepticism mixed with a growing sense of the common good? Whaterver the merits of "Informed cynicism," uninformed cynicism and half-baked conspiracy theories only feed the paranoia afflicting today's politics.

Three very different versions of national service were lumped together by Greider and denounced indiscriminately. Then, because the Ford Foundation gave a $45,000 grant to the Committee for the Study of National Service that Jacqueline Wexler and I chair,McGeorge Bundy was accused of "bankrolling a campaign for 'national service'" in "another liberal swing at 'forced integration.'"

Our committee, a project of the Potomac Institute, has issued its report, "Youth and the Needs of the Nation," and we are asking for debate. So we welcome Greider's hard questioning. But his broadsides bring to mind Lady Astor's comment when the iceberg hit the Titanic: "I asked for ice water but this is ridiculous."

LETS LOOK at the three contrasting approaches to national service that Greider sees as a single conspiracy:

1. A military draft : Sen. John Stennis and others alsrmed by the mounting problems of the all-velunteer aumed forces are calling for compulsory registration and at least a standby draft. Secretary of Defense Harold Brown has insisted that this time women should be included.

2. A universal draft for military AND NONMILITARY SERVICE . The editor of The Washington Monthly, former Peace Corps executive Charles Peters, has called for twe or more years of compulsory service for all yoyng men and wemen -- with options as to the form of military or civilian service. My daughter, a university student, agrees, arguing that her generation would grumble but do it, and that they and the country would benefit.

3. A move toward universal VOLUNTARY service . Young people would be called upon -- but not compelled -- to engage in a year or more of rull-time civiliam or military service. This is what our report proposes: the development of a voluntary system with a million or more new opportunities for nanmilitary youth service.

Arguments can be made for and against each plan, but the implications are strikingly different. The first plan is entirely military. It seeks just enough draftees to fill the armed forces. The second plan would require universal service but at a price that might be even higher than the financial cost: loss of the spirit of volunteering.

The third plan of voluntary service, which our committee recommends, would move towad universal service. But, like the goal of universal completion of high school, this goal would probably never be reached. Some who could contribute most or benefit most might not volunteer.

In sharp contrast to the proposal for a new military draft, the plan favored by our committee, through a variety of new institutional arrangements. would move the country toward a time when some form of boluntary service was the common expectation of every young person after leaving high school or college. Obviously, for such a system to work every sector of the society -- not government alone -- would have to be involved.

With such a system in place, a military draft in peacetime might never again be necessary. In a 1977 Gallup Poll, 43 percent of men aged 18 to 24 replied that if they were to engage in national service they would prefer military to nonmilitary options. Father Hesburgh of our committee was on the presidential commission that recommended the all-vol-unteer armed forces. Because our proposals would strengthen the volunteer spirit throughout American society and at all ages, he sees them as one way to make the volunteer system work.

Yet with a broad brush, William Greider includes our proposals in a plot to "force [his] children into involuntary servitude." The reverse is closer to the truth.

If large-scale voluntary national service does not take hold among the young, then before long the military may well have a compelling case for conscription The draft well seem preferable to the inadequacies and the astronomical costs of an increasingly mercenary armed force.

What about your children, William Greider? Wouldn't they want to have nonmilitary options? My sons do.

The McCloskey bill would provide these options by combining the carrot and the stick. Registration would be compulsory, but the choice of military or nonmilitary service would be voluntary -- as would the choice of not volunteering for either and taking your chance in a pool to be called in case a military draft should ever be required. Universal registration with strong inducements to wolunteering would probably assure that no one would ever need to be drafted.

GREIDER SUGGESTS that "Youth and the Needs of the Nation" was "cleverly drafted" to endorse voluntary service while covertly advancing "the real thing, a mandatory system." Again, the reverse is the case. Former senator Stuart Symington withdrew from out effort because we would not propose a compulsory plan.

As part of his conspiracy theory, Greider calls our committee's findings and the background study by Roger Landrum "the Ford report" and golds McGeorge Bundy responsible. He proposes that instead of asking his children, Ford Foundation president Bundy himself take " a year or two off to sweep up in nursing home."

Not a bad idea. It is intriguing to imagine presidents of foundations or colleges -- or newspaper editors and columnists -- working in nursing homes, or tutoring low-achieving students, helping in day-care centers, rehabilitating slums or tending our national forests.

But the Ford Foundation's grant to help cover the expenses of our committee's study does not make it a "Ford report." Bundy's only role in the project, when Jacqueline Wexler, president of Hunter College, and I proposed it, was to urge us to be sure we included experienced manpower economists and keen critics in our committee. Seven other foundations have given support to our efforts to stir a genuine national debate, but it is not their report either.

Willard Wirtz, Eddie Williams, Mildred Jeffrey, Bernard Anderson and the rest of our committee are not conspiring with anyone to restore conscription. We are an open conspiracy in search of the way to create a broad new avenue for youth to contribute to our society and to restore the spirit of service.