"It's only right that lefties unite," is a slogan that might have gotten a long hard look from the House Un-American Activities Committee back in the '50's.

Sinister is Latin for left and you know what that means.

The word "left" has also been linked with clumsiness by drill sergeants as when a recruit having trouble marching had "two left feet."

But the slogan has no political connotation nor awkwardness to Marcie Lewingstein who is left-handed and fighting a world that manufactures things geared to the right-handed.

When you meet Marit she holds out her left hand for a shake and you better hold your left hand to take it.

Lewenstein is a slight, still under thirty, nicely aggressive crusader who runs her "Left-Handed Compliments" push cart at Fanevil Hall Marketplace in Boston with a sense of humor and a firm purpose.

She is a former teacher and guidance counselor who quit the school system to run the stand and her crusade. "Because," she says, "schools are still backward in buying supplies and just the general helping of left-handed pupils."

She estimates that about 75,000 people may pass her push cart on a Saturday and out of that number 20 per cent might be left-handed. About 20 million Americans are probably left-handed, it is estimated. A message across the top of her brochure says. "I out of 5 people may be a lefty but 4 out of 5 people love someone who is."

Older left-handed people tell horror stories about the times a teacher or someone close to them tried to break them of being left-handed.

The techniques range from having their left hand tied behind their backs to getting whacked across the knuckles with a ruler - or even worse.

Many studies have been made, hundreds of tests have been written about the psychological effects of left-handedness on the individual so "afflicted."

One study called "Left-handedness and Cognitive Deficit," made by Curtis Hardyck. Lewis F. Petrinovich and Roy D. Goldman at the University of California said, "Willingness to believe in an association of deficit and left-handedness seems to persist, despite the considerable amount of evidence indicating the lack of any such associations."

John Marmos, who runs a card and gift shop here on 19th Street, has recently run a classified and urging left handed people to join him in a charge membership in an organization he is calling: "Left-Hander International." In only a few days he'd gotten 50 responses.

He said he'd been thinking about starting such a group for several years. "Why did I have to salute with the right hand when I was in the army?" he complained in a voice that sounded a bit querulous. He plans to put out a newsletter called "South Paw," and says, "Maybe we can eventually have formal dinners with the place settings reversed and even change protocol by having the guest of honor sit to the left."

Like most people with a just cause, Marmos has researched its history and come up the many important left-handers, including Ben Franklin, Charlie Chaplin and Judy Garland.

The complaints of the left-hander are justified and many. Some rate old and others as new as the position of the Washington Metro's fare card slot.

A left-handed waitress said she had trouble writing because her hand smeared across the ink. In her early years she never realized she was left-handed and explained it by saying, "when I was real little I had bad eyes. I squinted at the world and I just thought that everyone did and I guess I thought that everyone was left-handed also."

Studies by experts in the field have found by studying the brush strokes of paintings by some of the early masters that quite a few were left-handed, including Michelangelo.

In sports the left-hander is an equal and maybe an asset at first base in baseball. Left-handed pitchers are sought by managers, but they would rather not have a left-handed catcher, second or third basemen or shortstop.

A right-handed boxer who has had a string of successful fights against right-handers is usually dismayed when he finds his next opponent is what they call a "southpaw" who is going to keep a right jabbed into his face for most of the night.

Former President Truman, Ford, and Vice President Nelson Rockefellers were left-handed. It might be the first time in history, during Ford's term in office, that both the President and Vice-President were left-handed.

It is said that Rockeffeller's father pinned young Nelson's left arm to his shirt or suit coat to try and force him to use his right hand.

Lewinstein will tell you all of his while standing alongside her pushcart as she makes conversation between sales.

While there, a woman came to buy two spiral notebooks with the spirals on the left side (so that the person won't have to rest an arm on the tightly woven spirals).

Along with many other items Lewinstein sells rulers with numbers advancing from the right to avoid smearing when the left-handed person has to draw in line.

A pair of blunt training scissors for a child that Lewinstein felt should be a part of every classroom equipment sells for $2.25.

There are books and instructions with left-handed crochet patterns, guitar, needle point, embroidery, and knitting, along with manuals for teaching handwriting.

Also there were a ladies purse, keycases, pin-on buttons, can openers, and all sorts of servers, including butter knives, for left hand use.

How could a left-handed playboy be debonair as he struggles to open a bottle of wine if the corkscrew is groved in favor of the righty? Now there's a corkscrew that goes counterclockwise.

Lewinstein was especially happy about gravy, soup, and punch bowl ladles with double lips for pouring.

Cartoons adorn the push-cart with bright smiling faces and slogans like, "Left out? You have a right to be left."

The sporting equipment people have always recognized the need for the left-handed athletes and pioneered early to design the equipment.Most of us can remember some sand lot game where a kid always nick-named "Lefty," usually a pitcher, would stand on the mound looking awkward wearing a baseball glove designed for a righty, on the "wrong" hand.

At the end of August Marcie Lewinstein will not renew her contract for her push-cart with the Faneuil Hall Marketplace.

She plans on retrenching to her home in Brookline. Mass, and work only with mail orders.

When we parted I held out my right hand by mistake and she shook her head and held out her left. I could see her points as we shook and said goodbye.