It is a hurtful thing to have to publicly agree with South Carolina's Republican Sen. Strom Thurmond. For once in his long career of error, the antediluvian gentleman was right in opposing the IRS's proposal to take away tax-exempt status to private schools which discriminate.

The senator is arguing his case on grounds which are much too narrow. He's saying that since many schools couldn't or wouldn't comply they would be forced to close, thereby dumping a pea pot full of new students onto the public school systems and the taxpayers who support them.

That may or may not be true, but the taxpayers also support private schools in significant measure by not making them pay taxes. No one can say for sure if taxpayers would be helped or hurt if a large number of private schools were forced to close by the IRS's action. The situation would probably vary from community to community depending on how much unused classroom space is available.

No, there are more important and persuasive reasons for objecting to this idea, which has received considerable support from liberal and civil rights groups. The first is that it is abominably poor public policy to use the Internal Revenue Service for anything but collecting taxes.

Not that we don't do it. The tax code is hardly more than a compilation of gimmicks designed to help this industry or that, to provide capital here and there, to encourage investment in one sector of the economy or another. It has yet to be proved that this maze of exemptions, immunities and privileges serves any general good, although it indisputably serves the private good of those fortunate enough to be the beneficiaries.

Manipulating tax collection has at least a patina of neutrality about it, but to use it to further social and political goals is yet more questionable. We've already done that by exempting the great philanthropic foundations from taxation. At best the results have been meager; at worst the foundations have squandered the money they ought to have paid in taxes in a manner every bit as bad as the way Congress wastes the tax money actually paid into the Treasury.

The IRS should have no other function but to harvest taxes. Anything else is too dangerous. If private schools are to be forced to integrate, let Congress deal with the issue full on. Let a law be passed and let the Justice Department enforce it like any other law.

This begs the question as to whether private schools should be forced to integrate at all. For some, like Jewish schools, it would be next to impossible unless Sammy Davis Jr. has a lot more kids than he's talking about.

Upper-class private schools probably are reasonably well integrated.

They have both the money and the motivation to find black students. The poorer sort of private schools, the kind of intensely middle-class place set up or at least expanded as a result of court-ordered integration, isn't going to have the dough to offer black families scholarships for their children. These are the kinds of schools that will close and aybe they should close; there's no denying many of them exist only because their pupils' parents don't want their children associating with children of another race.

However, the point of civil rights legislation is to provide all our children and all our people with an equal chance and a real chance at good schooling, good employment and all the other yummy things in life; it's difficult to see how integrating even the most racist private school helps to achieve that goal.About all you can say of forcing some tight-sphinctered, nasty Calvinist school to integrate is that the little Aryans in the fourth grade will have to gaze on a black child. This may or may not improve the kids' racial attitudes, but should attitude improvement be the business of government or should justice and liberty?

Justice requires us to focus on the main business of making sure all our children are given the tools of competence for a full and enjoyable life; liberty requires us to put up with a wide variety of even the most despicable diversity.

Instead of dabbling in social policy, perhaps the IRS could confine itself to producing a simplified tax form.