China's most influential leader, Vice Premier Deng Xiaoping, has directed that China must catch up with Taiwan economically, before it can recapture the independent, U.S.-supported island, according to the text of a so-far unpublished speech.

The major address by Deng to several thousand officials in the Great Hall of the People on Jan. 16 appears to be one of the most blunt and far-reaching speeches given here since the early 1960s. It lays out China's agenda for the 1980s, putting unusual prominence for the first time since the 1950s on the need for world peace.

"Our politics and economic system are superior to Taiwan's and we must also achieve a certain degree of superiority over Taiwan in economic development. We cannot succeed without this," Deng said, according to an official text of the speech obtained from Chinese sources here. Deng called the recapture of Taiwan a "major task" for the 1980s, but in other parts of the speech he seemed pessimistic about China's ability to overtake the prosperous island in this century.

Along with economic development and reuniting with Taiwan, another major task Deng mentioned is "to oppose hegemonism [the Chinese code word for the influence of the Soviet Union] and safeguard world peace in international affairs." Deng's remarks seemed a marked departure from the days of Chairman Mao Tsetung when the Chinese were fond of celebrating turmoil and predicting world war.

In trying to cheer up "those comrades who feel our prospects are not bright," Deng revelaed that 2.9 million people who were in some way punished during the polticial battles of the last two decades have had their reputations, and in many cases their jobs, restored.

But he also admitted that this huge number of former officials returning to their offices has brought conflict and inefficiency.

"People should not grumble and reproach others," he said. "It has not been long since they returned to their work posts, while the comrades who have been at their posts all the time are also facing new problems, and they cannot become familiar with these things all at once."

Deng insisted that all efforts be spent on strenghtening the economy, but said such efforts would have to be put aside "if large-scale war breaks out." Despite his emphasis on the damage of such war, he asserted that "we won military and political victory" in the self-defense counterattack against Vietnam" in early 1979. He says the Chinese attack stabilized Southeast Asia and heleped stymie the Soviets.

The speech contains several pleas for increased education spending.

"A country such as Egypt has a population of only 40 million, but they spend several times more per capita on education than we do," he said. He said that China had less than a million university students while the "United States has 10 million . . . We should be able to cultivate more people with specialized talents if we had 2 or 3 million students studying at university."

On the question of dissent, Deng's remarks appeared unusually harsh and indicated fear that the smallest public demonstration might damage his program.

Of the wallposters on Peking's "Democracy Wall" moved to more restricted quarters in December, Deng said: "What would happen if we allowed such things to spread unchecked? There are examples of this in the world, also in China. Do not image that acting this way will not lead to chaos and do not regard the matter as of little importance. A few poeple can sabotage our great cause."

Deng complained that some prodemocracy, unofficial magazines, now mostly defunct, were "printed beautifully. Where did they get the paper?" He said. "Some of those who support these activities are party members, and quite a few of them are even officials. We must clearly tell these party members, their standpoint is extremely enrroneous and dangerous."

In the speech he announced that the party Central Committee would ask that the right to put up wallposters be removed from the state constitution, a remark the official text said was followed by applause.

Deng said when a foreigner recently asked him to define the "four modernizations," the slogan for China's economic drive, he said his goal was a per capita income of $1,000 by the year 2000. He said China's per capita income is "only something more than $200." Even the $1,000, which is equal to Taiwan's per capita income, would be less than what he said was the per capita income of $3,000 in Singapore and $2,000 in Hong Kong. But in China, he added, life would be comparatively better because a large part of the income would be "directly distributed to the people."

China would not, he emphasized, "carry our modernization in the manner of Taiwan, where the ecnomy is actually under the control of the Unites States."