President Reagan is giving two signals about his intentions toward arms-control negotiations with the Soviet Union, and one is getting in the way of the other.

Those who believe that new nuclear arms-control discussions between the superpowers are needed to limit and regulate the arms race ought to be encouraged by the dovish sounds coming from California in recent days.

The day before his reelection, Reagan told reporters in Sacramento that "disarmament and the reduction in the world of nuclear weapons" would be his No. 1 priority in a second term.

In an Election Day interview with The Washington Post, the president said he thought that the Soviets were ready to negotiate seriously. And the following day, when soft words no longer served a domestic political purpose, Reagan repeated his commitment to genuine arms-control negotiations with the Soviets.

That this commitment involves more than rhetoric was made clear in Santa Barbara two days after the election by a senior administration official, who disclosed that exploration had begun on a wide-ranging proposal for negotiations embracing half a dozen arms-control issues.

So far, so good. This so-called "umbrella approach," in which a variety of issues could be addressed in a single set of talks, offers the superpowers a face-saving opportunity to put behind them the failures of the last four years.

Soviet unwillingness to bargain seriously may be the fundamental reason for these failures. But the other signal given by Reagan last week overlooks U.S. contributions to the arms-control gridlock.

These contributions were Reagan's harsh rhetoric of his early presidency, since abandoned with no acknowledgement that it was damaging, and conflicts among his Cabinet officials and their presumed subordinates on the wisdom of making proposals that might be considered seriously by the Soviets.

"We don't have a conflict within the Cabinet," Reagan said at a news conference in Los Angeles the morning after his landslide victory. "We're united on the idea of arms control, and I don't know where all this talk came from. And we're prepared to go forward with the arms-control talks."

It would be sad, indeed, if the newly minted second-term president were dissembling when he made this statement. Sadder still, but true, is that he believes it.

Even though the bitter and bureaucratic conflicts within the administration on every aspect of every arms-control proposal have been chronicled in books, magazine articles, news stories, his advisers' memos and his defeated Democratic opponent's speeches, Reagan remains so steadfastly isolated from the conflict within his administration that he refuses to recognize its existence.

This is a basic trait of Reagan's governance and has its advantages when it is necessary to remove an official without leaving presidential fingerprints.

It is an axiom that Reagan never fires anyone, but it is also true that he has had three national security affairs advisers, two secretaries of state, two interior secretaries and two Environmental Protection Agency administrators during his first term.

Although he doesn't realize it, Reagan has had a slew of arms-control advisers, usually pulling in different directions. The Soviets had reason to conclude that most of them -- with the exceptions of the distinguished envoy Paul H. Nitze and Brent Scowcroft, President Gerald R. Ford's former national security adviser -- were not that interested in arms control.

This is one reason why administration officials who want Reagan to be a peace president are floating the names of Scowcroft or Nitze as envoys to join Secretary of State George P. Shultz in providing a coherent U.S. approach to arms control.

Now is the time, Mr. President. Now is the time to do for an arms-control agreement with the Soviet Union what President Richard M. Nixon did for a realistic approach to the People's Republic of China.

Now is the time to use your mandate for the purposes of peace. This means recognizing the conflict within your administration on the wisdom of arms control, a conflict that only presidential involvement can resolve. Reaganism of the Week: Asked Nov. 3 at the John Wayne home in Winterset, Iowa, how guerrillas could remove Nicaraguan officials from office without violence, Reagan replied, "You just say to the fellow that's sitting there in the office -- you're not in the office anymore."