PITY POOR ELAINE BENSON of East Hampton, Long Island, quoted in the papers as being unable to decide between John Lindsay and Elizabeth Holtzman when it comes to the Democratic senatorial primary: "As a woman, I'm tempted to support Liz Holtzman, and as a neighbor, I'm tempted to support John. It's hard to sort out." Maybe I can help. I suggest she choose on the basis of ability.

I know this is a shocking, hopelessly passe suggestion since more and more we are being told that a person is never just a person, but an emblem -- a representative of his or her sex, race,e, ethnic group and, in the case of poor John Lindsay, who has spent a lifetime in public service, his neighborhood. It is all right now to see a person as primarily white or black, male or female or any combination of the two, and exclude or include on that basis alone. What the person is as an individual seems somehow beside the point.

At the upcoming Democratic National Convention in New York, for instance, the whole notion of judging a person strictly on the basis of birth (sex, race, ethnic group) will be carried to its ridiculous extreme. The party has ordered that each state delegation be composed of men and women on an equal basis -- 50-50. This is based on the proposition that about half the people in the country are women (51.3 percent, in fact), that women have been discriminated against in the past and, perhaps most important of all, that women have been the envelope-lickers and neighborhood canvassers of the party but have been largely shut out of the more prestigious positions -- delegate, for instance.

All three propositions are beyond debate. And what is also beyond debate is the fact that unless something is done about discrimination -- something more than simply forbidding it -- the effects of it will not go away. They will persist.

This is the reason for affirmative action, quotas, minority recruiting and the whole bag of devices and programs that are intended to overcome the effects of past discrimination by what sometimes amounts to present discrimination -- a sort of end-justifies-the-means strategy. Whatever good is accomplished -- and in the case of blacks it might be enough to override qualms about what amounts to reverse discrimination -- comes at the cost of judging people not as individuals, but as representatives of groups.

In the case of women delegates in New York, for instance, they are being chosen in some cases not because of some ideology or their particular politics, or even because a women's issue is involved, but because they are women. They might be Carter women or Kennedy women, but what really matters is only that they are women. If there should (God forbid) be too many men in a particular delegation, then women are substituted until the delegation, like Noah's Ark, is balanced between the sexes.

Where once to be a female delegate was always a real honor, you would be forgiven for wondering now if some of the women you see on the convention floor got there on the basis of ability or the sheer happenstance of birth.

But the real danger of this remedy is that it suggests that the old type of thinking -- the sort of thinking that produced discrimination in the first place -- is correct. If women are to be accepted strictly because they are women, then in other circumstances they would be rejected for the same reason -- as women. If you are going to make a virtue out of sex then, with a little twist of the same logic, you can make it into a handicap.

Women were not discriminated against, after all, because men saw them as individuals who happened to be women, but as women first and individuals later. Thus, they were always willing to make exception for some women they knew -- mothers or sisters or wives, for instance. If these women did not fit the sterotype, it was not because the sterotype was wrong, but because these particular women were exceptions.

Now women, at least the Democratic women, are pushing the same line, only in reverse. They have a noble purpose and they are attempting to rectify a bad situation, but they are nonetheless asking that women be seen first and foremost as women -- everything else coming second. It is on this basis that they want to be selected as delegates. They ought to give it some thought.

It is strictly on this basis that they were once excluded.