let a thousand flowers bloom

A calque of Chinese 百花齊放，百家爭鳴 / 百花齐放，百家争鸣 (bǎihuā-qífàng, bǎijiā-zhēngmíng) ("let a hundred flowers bloom; let a hundred schools of thought contend"), from various speeches made by Mao Zedong during the 1950s.