Trekking across the University of Maryland campus, Earl Robinson looks like a visiting professor from Berkeley: His sun-bleached hair, sideburns down to the jaws, is streaked with gray; his pink epauleted sport shirt is artfully patched; his feet are shod with sandals.

"Frisbees are flying overhead, and nobody notices him. It's too nice a day and, anyway, who here would know that this guy wrote songs like "Joe Hill" and "The House I Live In. "Who here has even heard of them?

No matter, says the 67-year-old baladeer of class struggle, former communist turned believer in reincarnation and in vegetarianism. "These kids are looking inward, and that's where the answer are."

It's been a long road from the WPA's Camp Unity in New York (where Robinson wrote his "Ballad for Americans") to sunny Santa Barbara in southern California (where, recently, the rock group Three Dog Night recorded his "Black & White," which he expects to earn him $100,000 in royalties).

"I've found that not every rich person is a bastard," he says, "and some poor people are real a . . ."

That, of course, is the stuff that raises the hackles of the Old Lefties, and Robinson says he's changed his thinking a lot since moving to the land of disposable culture.

"I think living in California for a good part of my life has helped me work things out," he said.

Robinson remembers fondly the days of the Depression-fighthing WPA, particularly his work in his native New York City on the Federal Theater Project, a program that also gave work to Orson Welles and John Houseman.

"Those were the days," he says, "getting paid to do what was in your heart. It was the flowering of the arts in this country, men and women scattered all over and writing and painting and making photographs.

It was through the WPA that Robinson met Paul Robenson, the great black actor and singer, whose birthday Robinson marked at the Maryland campus yesterday in a memorial celebration.

"I had brought 'Ballad for Americans' to CBS, and one of the executives there said, 'Wouldn't Robeson knock the hell out of this?' When we met, he came up to me and said, 'I know one of your songs: "Joe Hill"' I think some of the kids know it today because Joanie Baez sang it in the movie 'Woodstock.'"

Robinson's life has had its share of controversy. Some of his friends felt uncomfortable about Frank Sinatra's recording of "The House I Live In" because of Sinatra's political leanings, but Robinson now says, "I don't really care who sings my stuff. It's there for everyone. I'm not part of the group that thinks Nixon, for example, should be in jail. He lost what he wanted most and that was probably punishment enough, not to mention that we got him out of office." In 1957, Robinson pleaded the Fifth Amendment in a House Un-American Activities subcommittee hearing, and a few months later his "Ballad for Americans" was deleted from a July 4 festival at the Washington Monument grounds.

'Funny," he says. "In 1940 that piece was performed at both the Republican National Convention and the Communist Nationl Convention."

Right now, Robinson is a believer in something called Reevaluation Counseling, which involves talking with another person and "bypassing the psychiatrists, because they're much too heady," a sort of 'I'm-Okay-You're Okay approach to life. Before that, he says, he was "heavily into Transactional Analysis.

"The Party was very much against psychiatry in the '30s. But a lot of things have changed. I don't think that class struggle is a very resourceful way of understanding anymore. The revolution is in the individual taking charge of his or her self. It requires looking at your self and really learning how to love yourself. You can then join in causes. You can argue a lot better.

"I think the object now should be to find agreements. I'm not bothering with the Marxist line anymore. I just went to sing for the minners. That's a clear issue. But arguments about American imperialism, that we're out to rule the world, I don't feel it."

Robinson certainly doesn't fee like a relic from the old days. The only the '60s, believe it or not, when all these young people were saying 'don't trust anyone over 30.' I think you have to change. Not all my old friends agree. Some of them are still around and when they heard Three Dog Night singing one of my songs on the radio, they didn't like it. I thought it was great. But you know that these old people are like. They think of music in a very classical sense, and they just don't like rock 'n' roll."