Three new books on Pauling, one of them a collection of his own words, begin with his bucolic childhood in Oregon, playing on farms, in abandoned smelters and behind the counters of general stores. When he was 10, his devoted father, a hard-working druggist, died, leaving him with his neurasthenic mother and his younger sisters. The boy retreated into the study of encyclopedias and chemistry. "Linus Pauling: A Life in Science and Politics," by Ted Goertzel, a professor of sociology at Rutgers University, and his son Ben, a mathematician who is a lecturer in cognitive science at the University of Western Australia, underscores this passage as the mainspring of Pauling's emotional life.

Pauling's cognitive life is considerably more joyful, its early development illustrated by an incident recounted both in the Goertzel biography and in "Force of Nature: The Life of Linus Pauling," by Thomas Hager, a former correspondent for The Journal of the American Medical Association. A picture of Jesus in Pauling's bedroom began to glow one night after he had been idly staring at it. He gazed just as long at other objects in the room, found that they also glowed, and concluded that the phenomenon was an optical illusion caused by retinal fatigue.

Despite the family's perilous finances and the opposition of his mother, Pauling managed to work his way through Oregon Agricultural College, so impressing his professors that he was recruited to teach chemistry while an undergraduate. Unfettered by faculty dating codes, he married one of his students, Ava Helen Miller, less than two years later. She proved an intelligent partner, raising their four children, insuring that he had time for his scientific work and, later, providing some of the impetus for his political activities.

In 1922, Pauling proceeded to take his Ph.D. at the newly established California Institute of Technology. Off to Europe on a Guggenheim fellowship, he came into heady contact with the nascent quantum mechanics of Schrodinger, Heisenberg, Pauli and Bohr. Brimming with ideas on his return to Caltech, he applied the indispensable new technique of X-ray crystallography to determine atomic sizes, bond lengths and angles, and the general structure of scores of crystals, publishing rules sufficient to exclude all but a few possible structures for any given crystal.

IN a groundbreaking 1931 paper, he employed his broad knowledge of chemistry, various mathematical approximations to the intractable quantum-mechanical equations and a dash of intuition to elucidate for the first time the physical nature of the chemical bond holding molecules together and to reconcile it with chemists' traditional views. Pauling was as effective an expositor and promoter of these scientific findings as he later proved to be of his political and nutritional enthusiasms. This is obvious from "Linus Pauling in His Own Words," a thoughtful selection of excerpts from Pauling's writings and speeches, edited by Barbara Marinacci, a consultant with the Linus Pauling Institute of Science and Medicine in Palo Alto, Calif. Pauling's prose is direct, devoid of panache or intimate revelation, yet his optimistic, ebullient public personality comes through strongly. Mr. Hager's extensively researched book is also engaging and readable, despite a touch of the gigantism to which biographies are prone these days. Trimmer and more sculptured, the Goertzels' book is psychologically more probing; it portrays Pauling as a bit of a narcissist.