IF THE FEDERAL Trade Commission hearings on television advertising for children, now being conducted in San Francisco, continue on their present lofty course, there is no telling where they will be by the time the hearings shift to Washington in a couple of weeks. On Monday, the commission heard Robert Liebert, a professor at the State University of New York at Stony Brook, testify that children may become skeptical of their parents if the parents try to dissuade them from buying sugar-coated cereals or stupid toys. At the apex of such a conflict, when a parent's word is pitted against that of the Fruit Loops parrot, for example, the result is "mistrust." Parents are discredited in their offspring's eyes if they try to match "their meager persuasive techniques against the might of television advertising."

On Tuesday, the commission, barely recovered from Mr. Liebert's astonishing testimony, heard from Seymour Banks, vice president of Leo Burnett U.S.A. Advertising. Using what appears to be a reverseshock technique, Mr. Banks told the commission: "Even if a child is deceived by an ad at age 4, what harm is done?" Deception develops skepticism, contends Mr. Banks, invoking the opposite kind of skepticism to that which concerned Prof. Liebert. How the FTC will deal with such polar opinions, we can't imagine.

On the narrow issue of whether or not TV advertising makes kids streetwise or anti-parent, we cannot comment with any confidence. Since there are only about five years in which children do trust their parents (the first five), it seems highly unlikely that little Amy will side against Mom, and with Cap'n Crunch, in the crunch, especially if one of Mom's "persuasive techniques" is the use of the word "No." On the other hand, we must say we have not noticed many dyed-in-the-wool skeptics of any sort among 5-year-olds, or even 8-year-olds -- agnostics, sure, but rarely skeptics. This may comment on our lack of experience, naturally. And the fact that we generally find kids to be twice as discriminating as their parents -- in an undemonstrative, unsociological way, to be sure -- is probably due to a faulty sample.

Needless to say, it's all very confusing and nerveracking. And whatever comes of these FTC hearings, at least the ever-expanding field of child telepathy may be further expanded. One thing is certain: If all future witnesses are as astute as the first two, we may prepare ourselves for quite a show -- one which, if televised, would draw a socko rating Saturday mornings.