My wife and I had dinner recently at a place we frequent. This time we were involuntary witnesses to the sexual abuse of a child.

The party at the adjoining table consisted of six persons — a couple of girls of about seven or eight, two youngish women, one of whom appeared to be the mother of the girls, and two men, perhaps in their fifties. One of the men positioned himself immediately to the left of one of the youngsters. Very soon he began to massage the girl’s back. Nothing untoward there, but then he slipped his hand down and inside the back of the girl’s shorts.

What might happen to that child in the privacy of a home or room? No one at the table appeared to notice the incident.

Nor did I call it to their attention. It was so unexpected I was at loss to know how to respond; if I objected it would have embarrassed the child and possibly triggered a brawl, and, at 84, I am not in the best of shape for pushing and shoving, so my wife and I simply exited the place, bothered as much by our failure to act as by the fondling. A couple of days later it occurred to me that I should at least have written a note and handed it to the woman I took to be the mother describing what I had witnessed.

The American Psychiatric Association says “children cannot consent to sexual activity with adults” and that an adult who engages in sexual activity with a child “is performing a criminal and immoral act which never can be considered normal or acceptable behavior.” In my unprofessional opinion, the activiy in a public place is especially sick.

My quandary about how to handle the abuse I witnessed ought to capture the attention of the advice industry. Abby and the other dispensers of canned wisdom for mass audiences ought not to to wait for letters from readers but to take the initiative with suggestions for how to react to the sexual abuse of children.

Tens of thousands of young girls are victimized sexually by adults each year in this country, most often by relatives. Silence in the face of it ought not to be an option. Yet when I witnessed it, that was the option I chose because I was dumbfounded and had no fund of advice to fall back on.

Granted, a man putting his hand down the pants of a young girl is not an everyday public occurrence. But forewarned is to be forearmed. Advice columnists, to your stations!