If sighting a robin in a January blizzard has a commercial equivalent, it's the scene of Christmas decorations in October. Shoppers in the 28 department stores of Carson Pirie Scott & Co., a Midwestern chain, had that marketplace shock on the first day of last month, a full 86 days before the birthday of Jesus.

By mid-October, with Santa's reindeer still foraging on the meadows of the north country, the Christmas-selling season had spread to Bloomingdale's. Then everywhere. Last week in Washington, with the temperatures hitting 80 degrees, an ad for Christmas trees ran in the classifieds.

'Tis the season to merchandise, and merchandise early, the better to soften the recessionary hard times expected for commercialists. In a calmer day, Christmas selling began the first weekend after Thanksgiving, an excess already. At the current rate of expansion, Santa could be in the malls and catalogues in the mails by the first weekend after Labor Day. Outlandish? Did anyone ever think it would begin Oct. 1?

This unprecedentedly early marketing of Christmas is another assault by American business into places where it has no business: Hollywood producers now routinely earn money through "product placements" -- displays of brand names in films. Colleges whore for corporate money through allowing commercial ties to sporting events: the Mobil Cotton Bowl, the Federal Express Orange Bowl, the Sunkist Fiesta Bowl. Computerized phone advertising is legal. Channel One, masquerading as a children's news program, delivers television ads to public-school classrooms. Philip Morris promoted "the year of the Constitution" with an essay contest on the First Amendment. Nearly 40 percent of all mail is unsolicited sales promotions.

These invasions into homes, schools, institutions and eardrums -- all of them once seen as preserves off-limits to pitchmen -- confirm William Wordsworth's poetic analysis: "Late and soon, getting and spending, we lay waste our powers." What's wasted are the powers to discriminate between what commercialists say people need, want and should have and what actually is justifiably required.

The forces promoting consumption are investing $130 billion in media advertising in 1990, a sum twice as high in 1982. Advertisers who are spending $520 a person to persuade him to buy, buy and buy need an ever-expanding marketplace -- an ever-larger Christmas season and more 24-hour shopping malls -- to take in the money.

Earlier this month, the Center for the Study of Commercialism, a Washington advocacy group, announced a campaign to organize citizens to "immunize themselves against the acquisitive mind-set fostered by the purveyors of 'more.' " Intelligently, it plans to advertise the economic facts about advertising, starting with the 100 percent deduction that companies are allowed for ad expenditures. A proposal to cut deductions was offered in the recent congressional budget debate, but with beer, cigarettes and air travel dominating the tax debate, advertisers were let off. This time.

The Center for the Study of Commercialism, a new venture, will succeed if it can show citizens that resisting advertising excesses is a positive, not a negative, act. It is breaking free of thing-reliance, the opposite of self-reliance and the major ailment for people who live in what G.K. Chesterton called "the kingdom of thingdom." What the center needs to advance, and it shows promise of wanting to jump in and do so, is the idea that spending time with a friend can be more satisfying than spending money, that sharing inexpensive homemade gifts with family and neighbors stirs the souls of givers and receivers more than exchanging overpriced luxuries, that consumerism is a debilitating ethic.

In the current World Watch magazine, Alan Durning writes in "How Much Is Enough?": "Accepting and living by sufficiency rather than excess offers a return to what is, culturally speaking, the human home: the ancient order of family, community, good work and good life; to a reverence for excellence of craftsmanship; to a true materialism that does not just care about things but cares for them; to communities worth spending a lifetime in."

We have let advertising con artists steer us away from that, while turning us into suckers for the idea that a rich life must be a moneyed life and simple living must be dull living. Give the conners credit for brazen boldness. They are using Christmas -- the birthday of a rabbi who said that happiness doesn't come from possessions -- to do the year's major hustling. Give them credit for that, but nothing else.