In the 1960s Pauling spent several years researching the problems of war and peace at the Center for the Study of Democratic Institutions at Santa Barbara, California. He also held appointments at the University of California at San Diego from 1967 to 1969 and at Stanford University from 1969 to 1973. His last appointment was as director of the Linus Pauling Institute of Science and Medicine in Menlo Park, California, from 1973 until his death in 1994. In 1980 the Linus Pauling Institute of Science and Medicine moved to Palo Alto, California.

        There is no question that Pauling was extremely intelligent, including both verbal and mathematical abilities. He had an outstanding ability to visualize spatial relationships. He was a creative, intuitive thinker, for whom new ideas came quickly and spontaneously. He contrasted himself to very capable scientists who got new ideas by "fiddling with the equations." By contrast, he said "I've never made a contribution that I didn't get just by having a new idea. Then I would fiddle with the equations to help support the new idea." His approach, as he often remarked, was to have a lot of ideas and then throw away the bad ones.

        He had two different intellectual styles in coping with this flow of ideas. In the first, he carefully tested his ideas against empirical data. In this mode, he was open to modifying or even abandoning his ideas if they were not supported. In this process, he often came up with new ideas. He used this mode of thinking in his work in chemistry, and more generally in work which did not involve a strong emotional dimension. He was at his best when he was solving scientific puzzles. In the second mode of thinking, he became emotionally committed to his ideas and selectively sought out evidence to support them. He became defensive against anyone who questioned his thinking on these matters, often assuming that they were motivated by personal animosity. He made the strongest case possible for his point of view, while minimizing contradictory evidence. His political and nutritional work often followed this second mode of thinking, and it was often effective in advocating for controversial positions.

        In contrast to his tremendous enjoyment of intellectual activity, Pauling found emotional life troublesome, and he often tried to avoid situations which involved emotionally charged interactions. He did this especially when he was young, largely as a way to avoid the demands of his mother and others who wanted to steer him away from his intellectual and scientific interests. Once he achieved success with his theory of the chemical bond, he allowed himself to become involved in issues which were emotionally charged for him. Rather than focusing on personal or family life, however, he felt most comfortable in the public arena where he could rely on his skill as a speaker and writer and his prestige as a scientist.

        A core element of Pauling's personality was a narcissistic tendency to overvalue his personal worth and seek the approval of others for his ideas and accomplishments. He loved giving speeches and receiving the approval of large groups of admirers, and he devoted a great deal of time and energy to travel and public speaking at the expense of his scientific work. His narcissism was displayed in an extreme sensitivity to criticism, including a tendency to file law suits against his critics.

        In his personal life, Pauling was stiff and formal, not the kind of person who enjoyed casual, lighthearted activities. He was happy to leave the responsibility for personal and social matters to his wife, to whom he was quite devoted. He did not spend much time on close friendships which involved meaningful interpersonal commitments. His wife was certain he would never have an affair, because he would not want to spend the time needed to romance a woman. He might have felt isolated or lonely, if it were not for the devoted companionship of his wife and the continual stream of attention from admirers around the world.