董仲舒的陰陽五行說，為漢代儒家系統理論的巨擘。然而，學者對董生陰陽五行說，尚未解決的問題有四。其一，董生學說中陰陽與五行，究屬何種聯結關係？陰陽與五行又可否分離獨立成說呢？其二，陰陽二者有無高下主從之別？陰陽說是否即如某些學者認為的中和說？其三，五行說與三統說如何配應？其四，董生的天人合一說的論證，有足夠論據證明其說否？解決了上述首三項問題以後，基本上已把董生的天人之說加以定位。至於第四條問題，則可窺見漢代儒學的天人關係的基本方向，自有其思想史的價值在焉。

Dong Zhongshu’s teachings on yin-yang and wuxing is a classic element of Han Confucian thought. Nevertheless, Dong’s teachings have caused four principal irresolvable questions among scholars. Firstly, what kind of association is there between yin-yang and wuxing in Dong’s eyes? Can yin-yang and wuxing be theorized separately? Secondly, is there any rank or order between yin and yang? Does the theory of yin-yang conform to the theory of zhonghe? Thirdly, how do the theories of wuxing and santong relate to each other? Finally, is there enough evidence to support Dong’s theory of the harmony between heaven and man? Dong’s theory of heaven and man is basically positioned once the first three aforementioned questions are addressed. The result of the fourth question can show that the fundamental direction of this theory makes an important contribution to the history of thought.