Normalization of relations between the United States and China will lead to an expansion of economic and cultural exchanges, but Americans should not ignore limits on these exchanges or the historical differences between the two nations, Harvard China experts said yesterday.

"The dangerous tradition in United States-China relations is that American expectations get too high and therefore disillusionment is around the corner," James C. Thomson Jr., curator of the Nieman Foundation, said yesterday.

"We should take this new development joyfully, but cautiously. Everything can always flipflop overnight," he added.

"China had opened up considerably in recent months," John K. Fairbank '29, Higginson Professor of History Emeritus, said yesterday. "The signing of the treaty is just one step."

Already

"Changes have already occurred," Edwin O. Reischauer, University Professor, said yesterday, citing student exchange programs and Chinese contracts with American companies.

But limits exist, Fairbank noted, and even if tourism grows immensely Americans still will not be able to wander about the Chinese countryside, because of lack of facilities as well as language difficulties.

Although China is eager to increase trade with foreign nations the United States is, "in terms of trade and commercial exchanges, only one on a list, with France and Japan ahead of us," Patrick G. Maddox, director of external affairs for the Council on East Asian Studies, said yesterday.

The agreement pleased the China experts, in spite of some initial fears about the safety of Taiwan. "It's about time and tragically long overdue," Thomson said.

The suddenness of the establishment of diplomatic relations and the breaking of formal ties with Taiwan surprised some. But after 30 years of support of Taiwan as the government of all China, recognition of the people's Republic was inevitable, Fairbank said.

Taiwan, in its belief that it will liberate the mainland, is "like somebody that's had a love affair and never gotten over it," Fairbank said.

The Chinese must have agreed informally not to be aggressive towards Taiwan, Benjamin I, Schwartz '38, Williams Professor of History and Political Science, said yesterday.

"There's no chance whatsoever that China can or will ever take Taiwan by force," Thomson said.

The agreement and Chinese contacts with several American firms represent attempts by China's deputy prime minister Teng Hsiao-ping. to institutionalize developments in U.S.-China relations, Maddox said.

"The Chinese realized that the United States has a lot of what they want and this is a way of getting those things, in writing," Maddox added