Everything you always loved and feared about Ronald Reagan was on display in the Great Performer's opening foray on the fall campaign trail.

Taken together, his six speeches last week might be called "The Collected Works of Ronald Reagan." He talked about high technology in California and family values in Utah, turning presidential just in time to pacify the business community in Chicago. Then he appeared in Washington in an old role as defender of Israel, to which he pledged undying support in a campaign speech as subtle as a used-car commercial.

It may be that there really is only one Reagan speech, with infinite variations. Reagan has been delivering it since he sold "progress . . . our most important product" for General Electric in the mid-1950s. Then, as now, Reagan praised the country and knocked government. Then, as now, he looked ahead to a boundless future in which Americans could do anything.

Last week, at two sun-drenched rallies in California, Reagan resurrected many of his oldest lines. He talked about "the puzzle palaces on the Potomac," as he did when campaigning for governor of California in 1966. He preached the virtues of "family, work, neighborhood, freedom and faith in God," a litany he used in 1976 and again when he won the presidency in 1980.

The speeches had some dubious passages. In one, Reagan offered "four great goals" that included one goal, one challenge and two assertions that were not goals. One of the assertions was the statement: "We will put forward a philosophy that proudly proclaims the rich traditional values that fill our lives and have permitted our nation to endure."

When Reagan did get specific, he turned to such second-line priorities as the line-item veto and enterprise zones. There are those who love these proposals, but Reagan did not get around to treating them seriously until the third year of his term.

The only time he deigned to answer a few carefully screened questions, before the Chicago Economic Club, he demonstrated that he didn't know his administration's estimates of the budget deficit or recognize that there have been eight budget surpluses since World War II.

Small wonder that Reagan has not held a news conference since July 24, that he is kept away from the news media lining the ropes, under the rubric of security, and sequestered at other times with no excuse at all. Reagan's handlers understand far better than his critics how uninformed he is on many of the day's major issues. It is not accidental that they have made him the most isolated president of modern times.

But none of that seemed to matter as Reagan widened his lead in the polls last week. His strengths overrode his weaknesses, as they have in past campaigns.

The first strength is Reagan's campaign staff, many of whose members, while not error-proof, are very good at what they do. They understand the importance of turning out a big crowd for television cameras. They know about providing balloons and backdrops and little lighting touches that show off a 73-year-old president to best advantage.

Another strength is Reagan's veteran political speech-writer, Kenneth Khachigian. For all of their homilies, speeches he wrote for Reagan in California qualify as minor masterpieces. They were stuffed with historical nuggets and patriotic references that Reagan loves, and they used a stiletto on Mondale instead of the broadax favored by speakers at the Republican National Convention. "America isn't about promises," Reagan said in a memorable line that made his case and the one against Mondale. "It never has been. America is about promise."

Later in the day, Reagan said: "We want to talk about the present and the future, about what Americans are doing together and what we must continue to do to make America great again and let the eagle soar."

The other strengths of the Reagan campaign are Reagan's. He has been delivering lines such as these for 30 years and believing them. He also said repeatedly last week that strength is necessary to deal with the Soviet Union and that Americans want and deserve less government. He believes these advocacies, too.

Reagan's speeches work on two levels. They work substantively because people know what he stands for on the great issues of the time, whether or not they agree with him. He is a constant in a world where politicians shift with the winds.

The speeches work even better symbolically. "We will continue to insist that there is no such thing as a life without uncharted frontiers and that it is our mission to seek them, not cringe from them," may not be "a great goal," but it is a resonant expression of American optimism.

Reagan's secret is that he understands this optimism, intuitively and deeply. He does indeed "let the eagle soar." He makes people feel good, not by providing a blueprint of the future but by touching the hopes and aspirations that Americans hold for themselves and their country.

That is Reagan's greatest political strength and is why he commands the emotional high ground in this campaign. Despite his vulnerabilities, it will not easily be wrested from him.

Reaganism of the Week: Speaking to a rally at De Anza Community College in Cupertino, Calif., last Monday, the president said, "You know, I hate to say this, but the age factor may play a part in this election. Not mine. It's their ideas are too old."