When President Derek C. Bok appointed an outspoken conservative as dean of the ideologically divided Law School in February, many said the decision flew in the face of conventional political wisdom.

"This was the worst possible choice Bok could have made," one left-wing professor said of Professor of Law Robert C. Clark's selection. "There is nobody in the faculty who is more likely to polarize the school."

While Bok's choice mystified most outside observers, those who work closely with the president say he has never been especially concerned with the popularity of his decisions.

"Derek isn't someone who opens a newspaper page every day to see how he came across the previous day," says Vice President for Alumni Affairs Fred L. Glimp '50. "He does his job. If that causes him to come across badly, I think he thinks that's part of the job."

In fact, Bok's colleagues say the 59-year-old president sees himself more as a judge than a consensus-builder, relying on his own intensive legalistic analysis to determine what is right and wrong.

Guided by what many say is supreme confidence in his approach, Bok stands by his conclusions, even--and often especially--when they are criticized. And Bok, after 18 years in office, is so protective of his decisions precisely because he approaches them with a rigid commitment to rational analysis.

Many say Bok's refusal to divest totally of Harvard's South Africa-related investments--despite more than a decade of pressure from campus and alumni activists--is typical of this attitude. The president's stand is so firm that his associates generally refer to divestment as a matter already settled, citing the effort they say Bok has put into examining the issue.

Observers say the key to Bok's confidence is rooted in his method; he demands that large volumes of information be filtered up to him through Harvard's bureacracy whenever a decision is required. When Bok is interested in a subject, he insists that his committees and advisors provide him with a thorough presentation of facts and arguments.

"You find yourself having to provide more information on alternatives than you typically would like to," says former Vice President for Financial Affairs Thomas O'Brien. "He doesn't want to just know your conclusions--he likes to know how you got there."

Bok is also notorious for demanding this information in writing.

"Derek gets his information best by reading, and he knows that," O'Brien says. "He's always been quite a stickler for getting things in writing. That requires a degree of thoughtfulness that is unusual. He doesn't like to handle issues in passing...He must have a deep-seated concern for ever seeming unprepared."

"I think he analyzes well from carefully prepared material," says Stanford University President Donald Kennedy '52, a close friend of Bok. "He's used to working with briefs, and he may have found it's the most effective way to work."

Most say Bok, a labor law scholar, typically handles a problem as he would a legal case. Colleagues like Ford Professor of Social Sciences Emeritus David Riesman '31 describe Bok as a "rationalist philosopher" who shows unusual concern for the structure and consistency of arguments.

Although these analyses are particularly time-consuming, Glimp says Bok "never seems to tire. He can keep up that style more hours a day than anyone else could."

Bok's faith in his own impartial thoroughness, many say, makes him lose patience with those who he feels have not put in the same effort, or those who he thinks fail to present a rational and dispassionate case.

This impatience often expresses itself as a disdain for activist rhetoric, and chants like "Derek Bok, get the word, this is not Johannesburg" only harden the president's resolve not to cave in to outside pressure.

"He won't change his position just because criticism becomes public," says Corporation member and Geyser University Professor Henry Rosovsky.

And within the administration, Bok's colleagues are more willing to rely on his judgment because he seems better prepared than other administrators.

"If he makes a decision and it's not a decision I would have made, my first reaction is to think that there's something I missed," says Riesman.

'A Great Deal of Autonomy'

Bok's fellow members of the Corporation--which has ultimate say on all areas of University policy--have quietly ceded much of their authority to the president because of his apparent thoroughness.

"When you've got someone in his position that you've got a lot of confidence in, he has a great deal of autonomy," O'Brien says.

And because he makes a point of preparing himself, observers say Bok is more willing to act against the recommendations of independent advisory committees when making deanship and faculty appointments.

For instance, Bok defied the majority of a Law faculty advisory committee in choosing Clark for the deanship, and has often overruled departmental recommendations in refusing to tenure scholars in the Faculty of Arts and Sciences.

Riesman says Bok usually reads junior faculty members' scholarly work himself before granting them lifetime posts.

"This is possible for a president at Carleton College or Williams, but it's very remarkable for the president of a great university," Riesman says.

Because of Bok's time-consuming self-reliance, co-workers say he often comes across as a distant figure, one who is more likely to fire off a quick substantive question than engage in office banter.

"Derek earns more respect than warmth and affection," O'Brien says. "I've never quite worked around anyone who was as free of gossip. Personalities were never something that fascinated him, as they almost always are in a university."

Bok's "austere" personality may stem from his upbringing, according to some who know him.

"He comes from a family of solemnity and seriousness," Riesman says, noting that Bok's mother was a friend of writers W.H. Auden and Christopher Isherwood. "He grew up in an environment of high seriousness, and he maintains that."

Curtis Bok, the president's father, was a Philadelphia judge known for his intellectual, patrician demeanor and an ability to remain above the city's machine politics. Some say his demanding court-room manner is reflected in his son's strict standards for evaluating arguments.

"[Curtis Bok] would not lightly permit lawyers to miss the law or to be misguided," says I. Raymond Kremer, who as a lawyer in the 1950s argued cases before Judge Bok.

Coming from this background, Bok had to work hard to acquire the constant mask of congeniality Harvard's presidency requires.

"He has more bonhomie than when he came in, more capacity for wit," Riesman says.

Even now, Bok prefers dealing quietly with individuals to mixing and mingling in large gatherings. While campus groups complain about Bok's inaccessibility, he is known for stopping to chat one-on-one with students he meets in the Yard, amiably questioning them about their experiences at Harvard.

"He's like a Dr. Jekyll and Mr. Hyde," says Cambridge Mayor Alfred E. Vellucci. "When he's in the business office, he's a frozen popsicle. But then when he's with people he's different."

Bok's public reserve extends to his relationship with the press. Unlike many university presidents, he is reluctant to use the media to get his views across, preferring to express himself through carefully worded reports and speeches.

"He does not want to expose Harvard to misinterpretation," O'Brien says. "He is very, very leery of being misunderstood, and is willing to accept all sorts of brickbats about aloofness and coldness in order to avoid that."

In addition, the pragmatic Bok has said he is wary of spending time preaching on matters that do not directly concern higher education.

"He likes to confine himself to issues on which he can really make a difference," says Rosovsky.

Making a difference is important to Bok, who sees the office of Harvard's presidency as a charge that demands careful stewardship.

"He seems to be very future-oriented and very analytical," Kennedy says. "He is very concerned about how the University will look a long way down the road."

And, after nearly two decades in office, Bok's view of Harvard's future has become just about the only one that matters.