Should Israel talk with the Palestine Liberation Organization? The question cannot begin to be addressed as long as the PLO continues to speak in two voices.

One voice, in English and directed at the West, draws falsely on a vocabulary of peace. The other, in Arabic and aimed at Arab countries, calls for a struggle to establish a Palestinian state and destroy Israel.For the Israeli government to entertain the idea of direct negotiations with the PLO under these circumstances would be foolish and irresponsible.

It is always important to listen to what leaders say at home, to their own people. True intentions are rarely revealed to external audiences. A case in point is the changing behavior of the Soviet Union.

For years, Moscow preached peace at the United Nations while calling at home for the destruction of "the capitalist West." Only now does Mikhail Gorbachev speak, in Russian and at home, of peace and co-existence, and only now can the West hope for real changes in Soviet policy.

No such change has occurred in the PLO's language. To Western audiences, the PLO portrays the Algiers resolution of the Palestine National Council as a renunciation of terrorism and the recognition of Israel's right to exist.

But speaking to the Arab world, in the pages of Al Siyasa, a Kuwaiti newspaper, Abu Iyad, the PLO's second in command, explained it this way:

"We swore that we would liberate even pre-'67 Palestine. We shall liberate Palestine stage by stage . . . The borders of our state as we declared it represent only part of our national aspirations. We will work to expand them in order to realize our aspirations for all the land of Palestine . . ."

Two weeks later, he declared in the same publication: "If the PLO succeeds in establishing a state in the West Bank and Gaza, it would not prevent the continuation of the struggle until the liberation of all of Palestine is achieved . . ."

George Habash, leader of the Popular Front for the Liberation of Palestine, who participated in the Palestinian National Council and approved its resolutions, said last Jan. 31:

"We believe that the international and Arab circumstances do not enable us to reach more than the establishment of a state on part of Palestine.

"We see in the Zionist Entity a racist, fascist entity with which we cannot live in peace. . . . There is no doubt that the Zionist Entity will be destroyed one day."

Obviously, the PLO has not abandoned its plan for the destruction of Israel by stages. It also has not renounced terrorism but continues to employ it, both in its attempts to silence any Palestinian who opposes its directives and in its persistent attempts to infiltrate Israel's border with Lebanon - six times, in fact, since the PLO supposedly renounced terrorism.

What, therefore, should we talk with the PLO about? The replacement of Israel with a state of Palestine? The phased plan to achieve that end? Or, perhaps, what kinds of terrorist attacks are legitimate?

Some in the West claim that the PLO's statements in Arabic are meant only for "internal consumption" and that we should listen only to the declarations in English. This is wishful thinking, and dangerous.

Peace can be reached between states. Direct negotiations are the means. The peace reached with the most prominent Arab state - Egypt - proves that through direct negotiations this is possible.

Israel's longest border is with Jordan, and negotiations with Jordan and the Palestinians in the territories could begin at once.