The quest for personal roots need proceed no farther than the perimeter of one's own life to yield rewarding insight or catharsis. Thus the new series called "Childhood" makes its debut on public TV tonight with a 60-minute dramatization of a Rudyard Kipling story entitled "Baa, Baa, Blacksheep."

This initial installment and the four others that will follow on consecutive Wednesday evenings are plays about childhood as seen through children's eyes, but they are by and for adults. Kids could watch and enjoy also, if they are up for something a little grittier than "Flintstones." One might say it's a series for adults of all ages. If the Kipling is a reliable harbinger, no one will come away without a stirred heart.

Though the series, drawing on a variety of authors and circumstances, is not unmindful of the more euphoric aspects of the child's world, this is not your sugar-and-spice view of our early years. "Baa, Baa, Blacksheep," for instance, in which Kipling sublimited his own anguished beginnings, is an acutely painful story of a boy cut off from parental warmth and subjected to the most wounding sorts of humiliation and malice. It is related, however, with such tact and compassion that in the end it seems more touching than grim. The pain becomes an emphatic link between the boy and one's own past. It is that specially magnified pain of the small person. All of us have experienced it to one degree another, and it is assuaged by the play's truthful understanding of its nature.

The story begins in India, where Punch, the 8-year-old protagonist, and his infant sister live with their parents. For reasons none too clear, the couple feels obliged to pack the kids off to England, where they are put in the care of the Greenlys, an ailing, kindly but ineffectual sailor and his stiff-necked tyrant of a wife. When the husband dies shortly after the kids' arrival, Punch finds himself the center of a tightening noose of persecution, meted out on every side by "Auntie" Rosa, the widow, by his schoolmates and his teacher. He learns that lies are a better survival tactic than honesty, and he is pushed to requite "punishment" with violence of his own. In the end, only the fortuitous intervention of a friendly doctor saves him from permanent blight, and leads to the recall of the parents.

In Max Harris, who plays Punch, director Mike Newell of England's Granada Television has found himself a child actor of astonishing gifts. Newell and cameraman Ray Goode go to lengths to display the action from Punch's perspective mainly, but they don't use any of the usual sentimental or melodramatic ploys. They don't have to with Harris around. His acting is so free of self-consciousness or mannerism, one has only to see and hear him to believe in Punch and his feelings. The rest of the cast is on a par with Harris, and they are all much abetted by Arthur Hopcraft's lean, telling script.

The program is introduced by series host Ingrid Bergman whose unassuming grace makes her ideal for the assignment. The remaining four dramas are adapted from the writings of H.E. Bates, Barbara Waring, George Ewart Evans, and Frank O'Connor."Baa, Baa, Blacksheep" can be seen tonight at 9 p.m. on Channel 26.