The death of Chiang Ching-kuo (''CCK,'' the international community has always called him) directs attention to assumptions about the Taiwan-China situation that Father Time has frazzled.

1. The first of these, of course, was that Taiwan would one day liberate Red China. During the very early '60s, serious observers -- for instance, Charles J. V. Murphy, who died only last week -- thought they could foresee a breakdown in Mao China: a military insurrection, aided by a Taiwanese beachhead, leading to the liberation of all of China.

It didn't happen and it didn't come near to happening. What did happen was the opening to China inaugurated by President Nixon. Four years after the Nixon trip, Mao Zedong was dead, and one month after that, the Gang of Four were seized and the reforms we all acknowledge and applaud were undertaken under Hua and Deng. It is simply not authoritatively known what would happen tomorrow if those reforms were vitiated, and 100-proof Maoism returned.

Here is how the future looked to CCK when, almost exactly 10 years ago, I interviewed him in Taiwan.

''I predict that before too long there will be a deep malcontent going on in the Chinese Communist regime,'' he said, ''just like the de-Stalinization campaign. . . . After Mao's death, the Chinese Communist regime cannot have firm control in all parts of China, neither Hua Guofeng nor Deng Xiaoping, or any of the other leaders has that ability. . . . In the future, the Chinese mainland will be disintegrated. There will be different power groups appearing on the mainland, some of them having contact with us. So this is the general scenario I foresee for our recovery of the mainland.''

2. During the 1970s, CCK and Taiwan suffered their great humiliation. It came in two stages. First, Taiwan was kicked out of the United Nations, a move our representative there at the time, Ambassador George Bush, was not able to prevent. The second humiliation was our own doing: President Jimmy Carter summoned the Taiwanese ambassador, so to speak, in the middle of the night and told him to get out.

It was widely suspected that the boycott of Taiwan would have a terminal effect on its role in the world. The big airlines began boycotting it; embassies were withdrawn; Taiwan was even prevented from sending its athletes to the Olympics. Objectively, it seemed as though diplomatic, economic and cultural isolation would topple the regime.

That did not happen. The United States stumbled upon a functioning deception that gave us, in effect, diplomatic representation in Taiwan. And the graduated liberal reforms of CCK combined with the industry and energy of the people to create a super-minipower. It is estimated that next year, Taiwan will export $100 billion of goods.

3. Far from demanding with increasing truculence the return of Taiwan to mainland China, the government of Deng let the matter . . . cool. There was never any suggestion that Taiwan was other than a province of the mainland. But the matter was not pressed to the point of increased hostilities. And in the past few years, CCK even permitted some Chinese living in Taiwan to visit the homeland.

It is a wonderful paradox we will now be seeing, during the period of official mourning. The Taiwanese will dutifully mourn the son of the leader of the Kuomintang movement, the death of the pretender to the throne of China. The Chinese, it is predicted, will seek not to antagonize the Taiwan leadership. Peking's motives are obvious: It does not wish to give encouragement to the movement within Taiwan for independence. If Peking now treats CCK as a departed native, the forces in Taipei that will stress and restress the unity of the two countries will be reinforced.

But the great myth, with the end of CCK, is now over. It was in 1895 that the Japanese occupied Taiwan. It was liberated in 1945. For only four years it was restored to China -- the China ruled by Chiang Kai-shek. Its resident population is 84 percent Taiwanese; its president, selected by CCK, is Taiwanese in origin. ''You mentioned,'' CCK said to me in 1977, ''the possibility of Taiwan being a separate political entity. The residents, the Chinese people in Taiwan, know very well that this alternative would mean self-destruction for them. They would not take this course of action.''

They would resist it, but the time is clearly at hand to blow the cobwebs of the one-China mystique to one side. Acclaim Taiwanese independence, legitimize its role, formalize our own relations with it and hope that someday in the future, what Chiang Kai-shek and CCK did for Taiwan, the successors to Deng will do for the mainland.