Summers’ penetrating intellect combined with these political skills would have made him a good Washington economist and a decent manager. Yet these adjustments alone would never have been enough to make Summers either cabinet secretary or Harvard president material. Rubin provided the final molding necessary to hoist Summers into the big leagues.

From the beginning, Rubin’s influence manifested itself in the trust he placed in Summers and the responsibilities he delegated to him. Rubin, the former Wall Street insider, valued Summers for his experience as an economist. “People, myself included, realized that he brought two things to the table,” Rubin says. “First there was the quality of his mind and his understanding of policy.”

Second, though, was the recognition that Summers had the tools and instincts to think politically—his capacity to see, as Rubin explains, “who would care about something, how others may react, realizing how to present an issue in a persuasive way.”

Rubin made Summers a particularly active and powerful deputy. Summers attended principal’s meetings, with the cabinet-level heads of other organizations, in Rubin’s place. He was given nearly final authority on a variety of issues, chief among them social security reform. Summers describes working very closely with Rubin, and developing similar views on most subjects. As a result, Summers said, “People found they could get one-stop shopping.”

But Rubin’s greatest contributions to Summers’ professional advancement was on a personal level. Summers looked at Rubin, friends say, and decided that he was a model to emulate.

In contrast to Summers’ sometimes brash and impatient style, Rubin was mellow, calm and careful, someone who could really foster personal connections. The partnership with Rubin allowed Summers to see how to further refine his consultative skills, how to court and placate members of Congress, and others who might present obstacles.

But other aspects of this style were not so easily mimicked. Summers took to what Gruber describes as the “Rubin-esque, down home approach,” a mixture of phrases such as “in my opinion” and interjections of “gee.” The approach, said Gruber, “never really fit.” But eventually, Summers was able to effect this general smoothening, Gruber says, “without losing his edge.”