程頤對張載心性思想之繼承和發展有三方面，一是人性 論，張載首提天地之性與氣質之性二重結構人性論，為儒學重構了 新的人性理論。二程繼承張載二重結構人性論的同時，對其作了調 整，將天地之性改為天命之性，完成理學人性論建構。二是心性關 係，張載認為性大心小，主張通過大心工夫，達至心性合一，即天 人合一的境界。程顥認為張載的以心知天容易導向外求，堅持心性 本一的思想；程頤主張的心性合一須由工夫實現，正與張載觀點相 合；張載、程頤與程顥的差異代表了理學兩種不同工夫路徑。三是 心知之學，張載提出知的三種類型，即見聞之知、德性所知與誠明 所知，程頤繼承了張載的見聞之知和德性所知，將德性所知變為德 性之知，不再提誠明所知。這既表明二者對知論建構的不同理解， 也表明理學知論的最終完成。

There are three aspects about Cheng Yi inherited and developed thought of Heart and Nature of Zhang Zai. Firstly, in terms of the theory of human nature, Zhang Zai put forward the dual-structure theory of human nature, that is “Tian Di Zhi Xing” and “Qi Zh i Zhi Xing”，and construct a new theory of human nature for Confucianism. Cheng Brothers carried on the dual-structure theory of human nature and changed “Tian Di Zhi Xing” into “Tian Ming Zhi Xing”. The construction of the theory of human nature for Neo-Confucianism was finally accomplished. Secondly, in terms of the relationship between Heart and Nature, Zhang Zai think that Nature is larger and Heart is smaller, and advocate to realize “Tian Ren He Yi” by the means of the enlarging Heart. However, Cheng Hao criticized that Zhang Zai’s idea could easily lead to “outward-looking”，so he insisted theory of “Heart and Nature being one”； Cheng Yi think that “Heart and Nature being one” must be realized by the practice. This view coincide with Zhang Zai. Difference between Zhang Zai, Cheng Yi and Cheng Hao represent two different ways of practice. Thirdly, in terms of mind and knowledge, Zhang Zai put forward three types of theory of knowledge, that is “Jian Wen Zhi Zhi” “De Xing Suo Zhi” and “Cheng Ming Suo Zhi”， Cheng Yi inherited this pair of categories，on one hand changed “De Xing Suo Zhi” into “De Xing Zhi Zhi”，on other hand did not mention“Cheng Ming Suo Zhi”. This did not only demonstrate different understandings of knowledge theory, but also indicated that theory of knowledge was accomplished.