As a student at Cambridge University in the dim and distant past, I once made the mistake of questioning the wisdom of some regulation or other that was getting in the way of my social plans. I can still see the smug, chill and utterly uncomprehending smile that fixed itself on my tutor's face. "Well, Miss Greenfield," she said, calling down a rockslide of history on my poor argument, "we've always done it that way." So much for the revolution. Next question, please.

A smiliar spirit has animated Washington's response, and that of a variety of feeder-line bureaucracies and establishments, to the Reagan administration's planned assault on the budget. We've always done it that way -- or at least for a few decades -- and the feeling here, made up in equal parts of hypocrisy and fatalism, has been that the technique can't, won't and shouldn't be drastically changed. I don't know, as I write, what the final proposed budget cuts will be. But I do know this: you can mark down the first two weeks in February as the time when people all over this city -- not just those ritually opposed to domestic budget cuts, but also those ritually and noisily in favor of them -- looked at each other with disbelief and said, with shared alarm, "My God, what if he isn't kidding?"

The key word here is "kidding," and it goes to the subject of that hypocrisy which has had so prominent a part in our national budget-cutting arguments up till now. I must confess that for some of us it is a truly warming experience to see political and business figures who have made a career of lambasting Uncle Sugar and his profligate ways having it slowly borne in upon them that their own subsidies have turned up in David Stockman's knitting. What appears to be radical in the Reagan-Stockman approach, what we are all still unwilling to credit, is the possibility that some relatively consistent and objective standards might be made the test of whether or not a program should be supported.

Stockman and Reagan may be dead wrong about the secondary effects some of their cuts would have and they may be viewing programs insensitively or harshly. But the political irreverence of their approach has already had its uses. It has forced people to forget the palaver, the verbal tricks they have been playing for decades, and get down to explaining and defending their own preferred government expenditures (if they can) in serious ways.

It's not just those subsidized people on the right who have been inveighing against deficit spending over the years, confident in the knowledge that nothing would be done about their own boodle, who are having to revise their arguments. It is also that colony of folks who have come to inhabit the lazy left, people who long ago stopped thinking about what they were supporting just as long as it could go by some irreproachable general name.

Science, art, education, anti-poverty, social welfare -- fraudulently, but in the name of all these purposes and pursuits, any number of costly, pointless and nest-feathering little enclaves have been financed that are simply not defensible in social-policy terms. The only way you can defend them is by hollering "social welfare!" or "education!" loud enough so that no one notices that all you are talking about is a lot of federal bucks helping to fly middle-class consultants from here to there for yet another conference and another report that will not provide a single thought, skill, book, idea, bandage or spoonful of food to those who could use them.

Can government at this late date really distinguish between the legitimate and essential programs, on the one hand, and, on the other, these unessential borderline scams? The fatalism that marks the other part of Washington's responses to the Reagan-Stockman assault is based on the assumption that it can't and/or doesn't want to. The domestic-budget argument theoretically engages conservatives versus liberals. In truth, the web of subsidies and support systems that has grown up over the years mixes these people up together and creates a common stake in perpetuating programs that already exist. All this has gotten more, not less, rigid and ingrained with the passage of time.

You can go to seminars now at respectable universities for instruction in how to write grant applications and work the levers of the federal-government dispensing programs. Downtown Washington is the scene of seemingly endless construction of new office buildings intended to house the headquarters of every lobby and interest and industry you can think of (and then some) -- the fragmentation of interest-group politics. That is the terrain on which this budget war is supposed to take place. Some 15 or so years back, John Gardner, then at HEW and newly in charge of making much of the Great Society go, was complaining about the iron triangles -- tripartite arrangements of bureaucrat, lobbyist and congressman that controlled federal expenditures and confounded efforts to make those expenditures more rational, humane and efficient.

That was then. Now is worse. Listen to your legislators talk about the political-action committee that finances their campaigns and pressures their activities ever after. Hear people in both the legislative and executive branches marvel, in total gloom, at the degree to which government action has become a series of recurrent struggles to paste together a special-interest-group coalition, good for some one-shot endeavor and needing to be created in some new form for the next maneuver. We sigh about these things in Washington. We write learnedly about how little it is possible to do to alter them. There are the "constraints." There are the "complexities." There is the terrible fact that -- deep down -- business, labor, academia, the professions and even the leadership of some organized supplicants rather like the thing the way it is: they know how to work it.

What is so radical (and doomed?) in the administration approach is this: they are committed to crashing through that layer of hypocrisy and that structure of legal payoffs that characterize our traditional budget building. And -- this is the weird part -- they actually think they can do it.