U.S. Appeals Court Judge Robert Heron Bork, President Reagan's nominee for the Supreme Court, is one of the principal intellectual architects of the conservative assault pursued by the administration against liberal judicial activism.

The burly, bearded former Marine, a heavy smoker who has been known to enjoy a martini at lunch, does not fit the stereotype of the Ivy League professor he once was. But ideas, and the clash of them, have always fascinated him.

In his writings, speeches and opinions, he has advocated judicial restraint and assailed liberal judges for inventing constitutional rights and substituting their preferences for those of elected officials.

Specifically, the 60-year-old Bork has criticized rulings in cases on the "one man, one vote" principle and the constitutional right to privacy -- including abortion. He also has expressed support for the death penalty and doubts about the exclusionary rule.

Bork has opposed efforts to open the courthouse doors to a wide assortment of lawsuits brought by groups from members of Congress to the homeless, insisting that it is improper for the court to referee societal disputes that should be resolved in other branches of government.

Bork, the only son of a purchasing agent for a Pittsburgh steel company, left a promising career and lucrative practice as an antitrust lawyer in Chicago after seven years to teach because, he told his wife then, "I wanted a more interesting life than this, something more intellectually challenging in the sense of large ideas."

In 1962, Bork, his wife and three young children moved to New Haven, Conn., where he spent most of the next 19 years teaching antitrust and constitutional law at Yale. During that time, he served four years as solicitor general, the government's top litigator, and gained national prominence in 1973 for his role in what became known as the "Saturday Night Massacre."

Never shy about expressing opinions, Bork recalls spending much of his time as a high school senior "reading books and arguing with people." The arguments often have been esoteric. In a series of interviews with The Washington Post three years ago, he remembered once staying up all night during his law school days, arguing the theory of "vertical integration" with his wife.

His hair color earned him the nickname "Red" during a stint in the Marines, when he guarded Chiang Kai-shek's supply lines after World War II, and he did not always align himself with conservatives.

Eugene V. Debs, the labor leader and socialist candidate for president, was a boyhood hero, Bork said in the interviews, which were conducted with the understanding that they not be used unless Bork was nominated to the court. His politics as a youth were, he said, "socialist to New Deal, somewhere in there." He cast his first vote for president for Adlai Stevenson in 1952, and distributed leaflets on a Chicago street corner for the liberal Democrat before his classes at the University of Chicago law school.

Judge Abner J. Mikva, a colleague on the federal appeals court here and a friend since their law school days, often jokes that the Marines transformed Bork into a staunch conservative.

But Bork said his thinking began to shift when he was in law school, which he attended mostly on the GI Bill and with university loans. It was there that he met free-market economist Aaron Director, brother-in-law of conservative economist Milton Friedman.

"I think probably Aaron Director had as much influence on my intellectual development than any man, ever," Bork recalled. "I was a socialist-liberal kid when I ran into him." Director's teachings showed him "theoretically why a socialist society is going to be a poorer society than a free-market society."

By the time Bork was appointed by Reagan to the appeals court in 1982, he had spent the better part of his professional career developing and espousing conservative rebuttals to the dominant liberal judicial theories.

Bork was born on March 1, 1927, in Pittsburgh and grew up in a suburb called Ben Avon. His family was of German ancestry, with a long tradition of farming in western Pennsylvania. He attended a large public high school for three years. "I went out for football in my sophomore year but I quit," he said. "I weighed 144 pounds, and I quickly discovered that I was going to make the first team in debate right away and I wasn't going to make the first team in football."

He was editor of the school newspaper in his junior year before attending Hotchkiss, a prestigious Connecticut prep school, from which he graduated in 1944.

Bork went to the University of Pittsburgh for a few months the next fall, but mostly waited for what he expected was a certain call from the military. In 1947, after two years in the Marines, he went to the University of Chicago, graduated, and stayed there for law school. He finished law school in 1953 after another two-year hitch with the Marines.

Bork's first ambition was to be a journalist, not a lawyer. He went to law school, he said, because Columbia University Graduate School of Journalism refused to send him an application.

"I stupidly thought I had to have a degree in journalism from Columbia" to be a reporter, he said. "I didn't know any journalists {then}, or I would have known better. So, I sent off to Columbia for an application blank" but officials refused to accept his Chicago undergraduate degree. "Columbia wrote back and said if you go anywhere else to college for two years and get an honest degree, we'll send you an application blank. So that ended my journalistic career and I went to law school."

After law school, Bork joined the prestigious Chicago firm of Kirkland & Ellis, but he felt the time there was not enough of an intellectual challenge.

"I mean, those guys {in the law firm} are intellectually challenged, but they're dealing with very fine points and I didn't go into the law for that," he said. He thought about teaching, but toyed one more time with journalism. "Some editors of Fortune came and talked to me and they were jumpy because they were afraid since I was a partner in a law firm, if I switched to journalism and didn't make it, then I'd be on their conscience -- what would they do with me, you know?

Bork, an imposing six-footer who seems stern and professorial at times in public appearances, can joke about how President Richard M. Nixon "recoiled" when he first saw this "bearded academic" in his office, or how he tried for years at Yale Law School to develop "a more general theory on when government may coerce, when the individual must be left alone, and so forth and so on."

"I kept at it for years," Bork said, even though his best friend, the late Yale professor and conservative legal scholar Alexander Bickel, "told me I was crazy. He was right, I was wrong."

Bork left Yale in 1981, shortly after his wife, the former Claire Davidson, died of cancer. "My children had gone off to college," he said, "my best friend {Bickel} had died before that and I just thought the time had come for me to change my environment."

Bork rejoined Kirkland & Ellis in its Washington office, but only for a few months before he was appointed to the bench by Reagan. During his time at Yale, Bork made numerous speeches at the American Enterprise Institute, the conservative think tank, and other organizations. At a luncheon speech in spring 1982 for Ethics and Public Policy, another conservative group, he met a staff member, a former nun named Mary Ellen Pohl, who later became his wife.

The woman giving him a ride to the speech "showed up with Mary Ellen in the car," he recalled. "So I met her and talked to her, but we didn't go out or anything. I met her again at a book-signing party at Kramer Books and she came to another organization where I was speaking, so I asked her out. First woman I went out with since my wife died."

They were married in October 1982.

Bork, though much admired by the right, has been criticized, sometimes sharply, by conservatives for his testimony against a bill that would declare a human embryo a person from the moment of conception and strip lower courts of power to review cases involving abortion. Bork said it would be unconstitutional for Congress to pass a law saying human life exists from the time of conception.

He was, much to his surprise and bemusement, mildly booed at a meeting last January at the conservative Federalist Society, when he said it was too late, that too many decisions had gone by, to have the Supreme Court roll back the New Deal.

In the interviews with The Post, Bork said he was "very unhappy" with the decisions of the Supreme Court under liberal Chief Justice Earl Warren, generally because there was "a general absence of reasoning and kind of an appearance of more political will than judicial reasoning. A lot of those opinions, you suffer endlessly trying to find a {legal} rationale in them."

Bork has criticized the Warren Court's famous "one man, one vote" reapportionment ruling in 1965, not so much for its result but "only because you can't get it out of the Constitution." As a political matter, he said, "It doesn't bother me."

"I think a judge is not an elected figure and his only mandate in this area is the Constitution. It's the only thing that gives him the right to govern. And if he begins to make up things that are not in the Constitution, then he is governing, in a sense, without being elected and without being accountable."

Bork has championed the Reagan administration's thesis that judges must stick to the "original intent" of the framers of the Constitution. In response to critics who argue that the world has changed in the last 200 years, Bork says the Constitution can accommodate the changes.

"For example," he said, "the First Amendment is there. Nobody thought about radio and television, but I think when radio and television come along, to say that I know they were talking about expression and its dissemination and therefore I will apply the First Amendment to radio and television, it's not a jump. That is just applying an existing constitutional value to a new technology."

On the Fourth Amendment, protecting against warrantless searches, Bork said, "Nobody foresaw electronic searches, but to the degree that the electronic search threatens the same kind of values that they wanted to protect, I've got no problem applying the Fourth Amendment to electronic searches. The fact that they didn't foresee technology change, that they didn't foresee all kinds of developments, doesn't mean that the values that they apply can't be applied to those new technologies, those new developments.

"My objection is to a judge creating wholly new values that they didn't put in the document," Bork said, "which is not to say that those new values shouldn't be put in a constitutional amendment if they want to, or they shouldn't be legislated or whatever."