Xiàndài shèhuì bú shì yīyuán de, érshì duōyuán de.
Modern society isn't monolithic; it's pluralistic.
Tips
usage
Don't confuse with 一元 = 'one yuan (currency).' This dictionary entry is the technical/abstract sense: contrasted with 二元 (binary), 多元 (pluralistic). Common in 一元论 'monism,' 一元方程 'univariate equation.'