Oppenheimer: the man, not the melodrama; Robert Oppenheimer: Letters and Recollections, edited by Alice Kimball Smith and Charles Weiner, Cambridge: Harvard University Press. $20

Probably J. Robert Oppenheimer was neither quite such a great scientist, nor such a pitiable martyr, nor such an insidiously flawed character as the various factions of legendmakers have portrayed him. His life story was not, after all, Sophoclean tragedy -- as he recognized better than anyone and even, at one point near the end, was impelled to declare specifically. But it should be quite enought that, beyond any doubt, he was one of the most fascinating men of the 20 th century.

There are plenty of Oppenheimer bigraphies on the shelves, good reading generally, yet all of them fixated on the famous facts, the bizzarre anecdotes, the quirks, the contradictions, the superlatives, and especially on the final melodrama of his fall from official grace.

"Robet Oppenheimer: Letters and Recollections," a selection of his early and midlife correspondence strung together with narrative notes by the editors, turns out to be a far better biographical document than the others, though not nearly so full of high theater.

Yes, he founded and ran the laboratory that built the first atom bomb; yes, he was a genius and a polymath of astonishing breadth; yes, he was by turns the most arrogant man and the most polite, the most scornful and the most considerate, that some acquaintances ever encountered; yes, he endured a kangaroo trial during the McCarthy era and was "convicted" of complicity (though not of treason) and lost his clearance to be privy to government secrets.

But these were episodes, noisy aberrations, while the reality of his life lay mainly elsewhere: That's what this quiet new book tells us.

Alice Kimball Smith and Charles Weiner have, besides giving us some wonderful letters, performed a valuable rectification of emphasis, a rectification emblemized by their decision to include no letters written later than November 1945, the month after Oppenheimer's retirement as director of Los Alamos.

This decision makes good sense, given the editors' purposes, for several reasons. Their subject was Oppenheimer the private man, Oppenheimer the physicist; after 1945 his life was no longer so private, and he was no longer a working physicist. He had become an administrator and Washington's chief consulting oracle on matters technological -- and then finally a Cause. His later correspondence was more voluminous, more formal, and more guarded.

Following him only just beyond Hiroshima, Smith and Weiner present a very complete book devoted to the serious scientist, the son and brother, the teacher , the friend and colleague, before he came under the shadow of great fame. Read Jung, or Stern, or better still the security hearing transcript to learn whether he ever subscribed to the Daily Worker, or why exactly he ragued against building the hydrogen bomb. Read these letters to se what sort of person he was.

For instance, in 1931, as a new faculty member at Berkeley, writing presciently to his younger brother, Frank:

"I think that the world in which we shall live these next thirty years will be a pretty restless and tormented place; I do not think that there will be much of a compromise possible between being of it, and being not of it."

Many of the most revealing letters were addressed to Frank Oppenheimer, eight years younger, to whom Robert was extremely close. And nothing in the entire collection surpasses one passage written to Frank, then a confused 19-year-old, by the elder brother, in 1932:

"You put a hard question on the virtue of discipline. What you say is true: I do value it -- and I think that you do too -- more than for its earthly fruit, proficiency. I think that one can give only a metaphysical ground for this evaluation; but the variety of metaphysics which gave an answer to your question has been very great, the metaphysics themselves very disparate: the bhagavad gita, Ecclesiastes, the Stoa, the beginning of the Laws, Hugo of St. Victor, St. Thomas, John of the Cross, Spinoza. This very great disparity suggests that the fact that discipline is good for the soul is more fundamental than any of the grounds given for its goodness. I believe that through discipline, though not through discipline alone, we can achieve serenity, and a certain small but precious measure of freedom from the accidents of incarnation, and charity, and that detachment which preserves the world which it renounces. I believe that through discipline we learn to preserve what is essential to our happiness in more and more adverse circumstances, and to abandon with simplicity what would else have seemed to us indispensable. . . . Therefore I think that all things which evoke discipline: study, and our duties to men and to the commonwealth, war, and personal hardship, and even the need for subsistence, ought to be greeted by us with profound gratitude; for only through them can we attain to the least detachment; and only so can we know peace.

". . . You might like to try your Spanish on Unamuno: Del sentimiento tragico de la vida. And Jane Austen; do you know her six marvelous novels?"

Here, just possibly, in a fine collection of private thoughts and private words, is the heart of the matter of J. Robert Oppenheimer.