ONE DAY IN 1954, a 24-year-old private first class, Ira Levin, chanced to glance up from his desk in the public information office of a New Jersey Army camp just as the commanding general passed the door. It occurred to Levin then, for the first time, that the General, after all was a human being. And he began to wonder what sort of a human being the General was. What was his life like, what forces drove him?

The fruit of Levin’s speculation may be seen at the Shubert Theater beginning Thursday. It is a play titled “General Seeger,” and as Levin Is the first to admit, it probably bears little resemblance to the original General. Levin cannot be sure, for he never saw the General again; the whole play is a product of the New York playwright's imagination.

BEYOND that first glimmer. the instant the seed was planted, Levin can no more say how his play came to be than anyone else can.

“I've often tried to think how a play starts, or how any kind of writing starts, but I really don't know,” Levin said. “I keep a pad and pencil by my bedside and I write things down at three in the morning, but they’re rarely much help. Did you ever read anything you’d written at three In the morning?”

Other times, Levin says, “I hatch plots in my mind, I develop a story, but most of the time I throw them away. The Interesting thing is that an idea always seems to come when you're not looking for it. That still doesn’t help me, though; I still keep plotting and working things out in my mind.”

WHILE Levin began thinking in 1954 of the General who was to become Seeger, it was another four years before he wrote the play. “It was just there, in my mind, for those four years,” Levin said, “and finally, one day, it began to be a story.”

While a play script appears to be little more than a few scraps of dialog and a stage direction here and there, Levin assures you that it is more than that. “It took me four months to do Seeger,” he said. “That means from about 10 a.m. to 6 p.m. I wasn’t married then, either, so that meant I worked at it on Sundays, too. By the time I was through, I knew in my mind what the characters looked like, how they talked, what motivated them.”

HIS IDEAS have undergone considerable change in the three weeks that “Seeger” has been in rehearsal here. He has discovered the director George Scott has some ideas of his own, and so do William Bendix, who plays Seeger, and Ann Harding, who plays his wife.

The other day Levin was standing in the back of the Latin Quarter, where “Seeger” was being rehearsed for a few days, watching Bendix speaking on stage. “I can see how some of my ideas are changing a little,” Levin said. “Now, when I think of Seeger I think of Bendix. He's going to be wonderful in this, I think. It’s exciting to watch him and Scott work.”

BENDIX and Scott stopped rehearsing and held a quick conference. Bendix wanted to drop a one-word line: “Why?”—and so Levin was called down by Scott. After two minutes passed, along with some muttering, Levin returned. “We’ll cut it I guess,” he said. “I want to do as little changing as possible, but this may be necessary. A playwright is lucky if he ends up with 80 per cent of his own play left by the time it’s produced, I figure I’ll have about 96 per cent.”

AS LEVIN describes it, “Seeger” tells of a General’s investigation into the death of his son and the impact the investigation has had on the General. “But it goes deeper than that, too,” Levin said. “It is about people who accept any way of life without questioning it. A general might be like that, but so could many other people—a corporation officer, a man in a political party.”

“SEEGER” is the third stage play Levin has written. Each play has come about in a different way. His first Broadway play was an adaption of Mac Hyman’s novel, “No Time For Sergeants.” Levin had been writing for television, and he was assigned by the Steel Hour to do a TV adaptation of “Sergeants.” He then got an offer to do the stage version.

After that came his first original Broadway play, “Critic’s Choice.” “I was just reading a book one day by Walter Kerr,” (the New York Herald-Tribune’s drama critic) said Levin, “and he was telling about being married to a playwright.”(Humorist Jean Kerr.)

“In one paragraph of his book, he issued sort of a challenge: Somebody ought to write a play about a drama critic married to a playwright. I started to think about it and then just went to work on it.” Levin said he wrote the play with Henry Fonda in mind for the lead role, that of the critic. The role was offered to Fonda, who liked it and played it on Broadway.

LEVIN began to write while he was in school at New York University. In his senior year, he entered a half-hour mystery script in a CBS contest, and was runner-up He sold the script ot NBC for a mystery series, and was on his way—if a playwright is ever on his way. “It’s not the kind of job where you can plan for the future,” Levin said. “You don’t know from one play to the next whether you’re going to make any money or not.”

After success the first time out with the half-hour mystery, he wrote five or six scripts, and then a novel, which won the top mystery novel prize, and was turned into a movie.

AT 32, Levin, tall, dark, quiet, has found a pretty satisfying way of life. Yet, he is still experimenting, still hunting for the thing he would like best.