IN its drive to develop a market economy, China should maintain vigilance over the rampant growth of social evils and the infiltration of decadent thoughts, says a prominent economist. Yuan Bohua, president of the Chinese Enterprises Management Association, called for great attention to be paid to the drift of economic reforms into ''erroneous areas''. He said it was an error to think the development of a market economy could solve everything. ''Don't just see the positive functions of a market economy and neglect its negative side,'' said Mr Yuan, according to a China News Service report. He said economic growth could result in common affluence as well as the polarisation of wealth, adding that a socialist country could only choose the first direction. It was also wrong to assume the country would be peaceful after the economy had been developed, he said. Mr Yuan warned that people who got more money in their hands could indulge in extravagance and pleasure-seeking as well as money-worshipping. The opening of the doors of China would let in ''mosquitoes'' and ''flies'', he said, referring to social evils such as gambling, drug trafficking and prostitution. ''We can never pay the price of an immoral society for economic growth,'' he said. Insisting that the momentum of economic reforms must not be halted, Mr Yuan underscored the importance of reforms to the management and structure of enterprises. ''The major component of a market is enterprises. The rejuvenation of the operation of enterprises should be taken as the first and foremost task in the development of a socialist market economy.'' The macro control power of central government would be greatly weakened if enterprises, particularly state-owned firms, were unable to compete in markets, he said. Mr Yuan said the democratic rights of workers in enterprises should not become ''empty words''. ''Workers should be the masters of enterprises,'' he said. Workers must have the right to scrutinise and decide major policies and to have a say on the appointment and dismissal of cadres, he added. Mr Yuan said the development of China's enterprises had been slow because of outdated machinery, huge pensions for retired workers, and loans.