宋明理学是在北宋传统经学向义理之学转型的学术风气中形成的新的儒学形态。理学家因应时代问题，回归经典之源，通过对经典的重新诠释完成了思想的当代性重建，真正实现了天人贯通。其中，《周易》“推天道以明人事”的主旨以及关于天道、性命的论述，最终成为促成理学“天道性命相贯通”的重要思想资源。因此，北宋的易学诠释与理学思想体系的建构是一个过程的两个层面。周、张、二程作为理学形成期的关键人物，其对天道、心性问题的探究与理学理论的架构大体都是基于对《周易》的研究和阐发而展开的。虽然周、张、二程的哲学理论内涵有着明显的差异，但他们却有着共同的时代问题意识，即为儒家价值秩序寻求天道层面的奠基，回应释老以“空”、“无”为本的世界观与价值取向。在这一问题的指引下，四子分别借助相关易学命题来展开理学本体论的探究，形成了一条前后相继、不断演进完善的本体论发展路径。 周敦颐以《易》会通《中庸》，立“太极”为天道之本，立“诚”为圣人之本，第一次做了试图贯通天道性命的理论尝试，并首次关注到“理性命”问题，开启了天道为人性奠基之理学善端。张载明确提出“易乃性与天道”。他从《说卦传》“参天两地”中分析出“太极”“一物两体”的结构，同时也是“太虚”之结构。接着将“太虚”作为人与万物之源，以及“仁之原”，“心之实”，确立“太虚”为天道本体。人性之本也被追踪到“太虚”，并承继了“太虚”之“一物两体”的结构，而具有“天地之性”与“气质之性”的双重结构。张载说“性与天道合一存乎诚”，天与人在结构与内涵上都是一致的，由此构建了天道内在于人性的下行路线与人上达天道的上行路线，真正达到了天人贯通。程颢以《系辞》“生生之谓易”诠释“天理”，赋予天道“生生之理”的内涵。程颐通过“所以阴阳者，道也”的命题将“天地之道”转换为“万物之理”，又提出“万理归于一理”确立了“理”本体的地位。在人性论上，他诠释“继之者善，成之者性”曰“斯理也，成之在人则为人之性”，将天道本体之“理”规定为人性之内容，所谓“性即理”，达成了天道性命的贯通。周、张、二程的逻辑演进，清楚地表明宋儒贯通天道性命的一致努力在二程的“性即理”这里得到了彻底的实现。 总之，本着强烈的本体意识与为人世价值寻求天道奠基的问题意识，周、张、二程进入了融合《周易》与传统儒学的理论创造之路，他们的本体论建构和张载、二程在理论建构中对佛老的批判，皆是对北宋时代课题的有力回应。

Neo-Confucianism is a new pattern of Confucianism which is formed in the transformation atmosphere of traditional academic in the Song Dynasty. Neo-Confucians completed the contemporary implementation of traditional thoughts by returning to the source of the classic and following the needs of time， which truly achieve the uniting of heaven and human. In the meantime， the substance of Zhou Yi which is "exploring the regular of heaven aims to guiding personnel" and the discussion of life and heaven， eventually become the important resources of Neo-Confucianism which achieve the uniting of heaven and human. Therefore， the interpretation of the Yi in the Northern Song Dynasty and the construction of Neo-Confucianism system is the two levels of a process. As the key Confucians during the formation of Neo-Confucianism， Zhou Dunyi， Zhang Zai， Cheng Hao and Cheng Yi both explore the problems of of heaven and human nature to construct the system of Neo-Confucianism by studying and elucidating Zhou Yi. Although the philosophy connotation of them are obviously different， they have a common consciousness of time problems. They aim to seek the based level of heaven for the traditional Confucian value， which response to the world view and value orientation of "empty"， "no" of Buddhism and Taoism. Under the guidance of this issue， Zhou Dunyi， Zhang Zai， Cheng Hao and Cheng Yi form a succession and evolve ontology path with the aid of Yi and the discussion of ontological thesis. Zhou Dunyi combined Yi and The doctrine of the mean. He set "Tai Ji" as the foundation of the heaven and the "honesty" as the foundation of the Saints， which is the first time of theory attempt to uniting the heaven and human. Zhang Zai clearly put forward "Yi is the nature and heaven". Firstly， he established "Tai Xu" as the heaven ontology and the source of human beings and all things. Then he tracked the essence of human nature to "Tai Xu"， and the human nature structure is divided into "the nature of heaven and earth" and "the nature of temperament" by the basis of “there is the name of nature by combining virtual and spirit". Zhang Zai truly achieved the uniting of heaven and human by constructing the heaven downward path inherent in human nature and humanity reaching to the heaven upward route， which is said that " the nature and heaven combined in honesty”. Cheng Hao endowed with the connotation of the "living" to heaven by interpreting the “living means Yi” with the “principle of living”. Cheng Yi transformed the "the way of heaven and earth" into "the principle of everything" through the proposition of "Tao means the reason of Yin and Yang". Based on it， he established "principle" as the ontology status by putting forward "the principle of everything is one principle ". On the theory of human nature， he stipulated the principle of heaven as the content of human nature， said that “this principle inherited by human is the nature”. the evolution of the logic of Zhou Dunyi， Zhang Zai， Cheng Hao and Cheng Yi made it clear that the efforts of uniting the heaven and human of Confucians in Song Dynasty is completely implemented in Cheng Hao and Cheng Yi. In short， with a strong sense of ontology and the problem consciousness of seeking heaven foundation for the value of traditional Confucianism， Zhou Dunyi， Zhang Zai， Cheng Hao and Cheng Yi stepped on the road of creating the Neo-Confucianism theory. Both their ontology construction and the criticism of Buddhism and Taoism are the powerful response to the time needs of the Northern Song Dynasty.