双百方针

shuāng bǎi fāng zhēn

refers to 百花運動|百花运动[Bai3 hua1 Yun4 dong4] with its slogan 百花齊放,百家爭鳴|百花齐放,百家争鸣

shuāng

two

bǎi

hundred

fāng

square

zhēn

variant of 針|针[zhen1], needle