“学为人”是刘宗周思想的核心问题，杜维明先生曾以人学宇宙论来说明刘宗周的“哲学性格”。“学为人”的问题关涉到人的本质、人的实现与境界等诸多方面，据此，本文将刘宗周思想称为“人学”。本文从四个方面论述了刘宗周的人学体系：人性与人心——为人之根据；诚意与慎独——证人之工夫；圣学三关与迁善改过——为人之实践；生死超越与万物一体——成人之境界。这四方面构成了本文的四个章节。

第一章考察刘宗周的心性论。首节由王阳明“四句教”之“无善无恶心之体”这一引起中晚明学者广泛讨论的问题切入，引出刘宗周对性体的看法。刘宗周提出“性无性”之说，他反对悬空论性，认为性乃“心之性”，性是心的本质规定，它就展开于人心的道德活动之中。其次，刘宗周也反对将性分为气质之性与义理之性的做法，他认为，义理即是气质之性。通过消解性的独立性，刘宗周彻底隔绝了学者空寻性体的可能。次节着重讨论刘宗周在人心结构及其活动机制上的观点。刘宗周认为心是气的流行。气的流行以“独体”为枢纽，表现为喜怒哀乐四气。不断运动的四气，感于外则表现为仁义礼智与七情。心是与气、理（性）、物贯穿于一起的多面体。就其活动而言，心是一个具有感通能力的虚体，它在活动中会表现为思、虑、想、识、念、意等。刘宗周着重对意与念进行了区分。他认为，意有主而念无主；意无起灭而念有起灭；意为心之所存，念为心感物而发；先儒所谓意，即其所谓念。根据刘宗周对心性的理解，个体只能于心的活动中证显人之为人的规定性，这是其整个人学思想的理论基石。

第二章讨论刘宗周的诚意、慎独说，此问题既建基于上章的心性论，又为下章的实践方法提供理论依据，是刘宗周人学思想的关键。在诚意问题上，刘宗周以好恶这种人心最原发的本能活动指称意。刘宗周所说之意的原发性与意向性所显示的意义常为现代学者所忽视。刘宗周认为，意所显现的好善恶恶之意向性，使人在与经验世界沟通时，会缘境而表现出种种道德意向与活动。意是所有德性产生的内在根据与动力之源。因此，意既是德性之源，又具有好恶的活动能力，它可以统摄本体与工夫两个方面。基于此，他认为诚意为《大学》之“专义”“了义”，“格致为诚意而设”。第二节从“对越”的角度论述了刘宗周的慎独说。刘宗周既反对朱熹仅将慎独视为已发工夫，又警觉到王阳明以良知解独所造成的弊端。一方面，他摄性归心，使独体成为性与心的纽结之处，在以性贞定独体之价值意义的同时，又从心的角度赋予独体以活动能力。另一方面，刘宗周以动念省察、葆任存养、真实不欺为“慎”的三重含义，构建起慎独工夫的内在结构，使慎与独成为双向回环、两端互成的关系。学者往往未注意到刘宗周思想中的“对越”与“慎”的关系，及其所具有的工夫论意义。刘宗周所说的“对越”即是解除习染之蔽，还原独体之“本来真面目”，证显独体活动性的历程。在刘宗周的思想中，意与独都具有本体意义，但是意重在从心的活动上来讲，独则重在从性的角度来说。刘宗周的慎独、诚意说是其心性论在工夫论层面的展开。

第三章从圣学三关与迁善改过两方面，阐述了刘宗周人学思想中成人的实践方法。本章主要依据《圣学吃紧三关》与《人谱》两个文本展开讨论。《圣学吃紧三关》指明了实践工夫的三个宗旨：一、践履是以实现自身为终极目的的为己之学。二、慎独、诚意说在践履方法上体现为敬，敬则诚，诚则天。三、践履的意义在使人由敬入悟，证成自身。《人谱》以慎独说为灵魂，分析了人的六种过错，六过以微过为根，构成一个层层递进的套娃式结构。针对此，《人谱》提出了“六事功课”的改过方案，讼过是最根本的改过途径。

第四章论述刘宗周的生死观与万物一体之说，展现个体在成“人”后的终极关怀与境界。在生死问题上。刘宗周认为，常人总以私的方式与他者打交道，由此造成自我与他者的隔绝，生死成为囚禁生命的牢笼，忧惧成为基本的情绪状态。通过慎独工夫，个体以敬畏破私欲，以至于无惧，进而出离生死执着，复归本真生存状态。个体在本真生存状态中，既个别化自身又与物为一，并能以中正平和之情顺应万物，在寓死于生中体认生死之同一，最终栖息于道的永恒之家中。刘宗周的万物一体之说包含本体论、工夫论与境界论三个层面。生生之仁是万物一体说的本体依据。刘宗周特别强调由践履工夫达至万物一体之境，反对识得本体，即可与物为一的观点。

刘宗周的人学思想对“学为人”的问题给出了完整的答案。这对于转变当时的士风、学风起了很大的作用，甚至了影响了清代学术的发展走向。

"Learning to be human" is the core issue of Liu Zongzhou's thought. Mr. Du Weiming once explained Liu Zongzhou's "philosophical character" with the humanities cosmology. The problem of “learning to be a human” is related to the essence of human, the realization and realm of human and so on. This paper discusses Liu Zongzhou's humanities system from four aspects: human nature and human heartmind that are the basis of being a human; Chengyi and Shendu that are the Kungfu of being a human; the three junctures of being sage and the way of repentance which are the practice of being a person; The transcendence of life and death and the integration of all things which refers to realm of human. These four aspects constitute the four chapters of this paper.

The first chapter researches Liu Zongzhou's mind-nature theory. The first section begins discussing from "no good and no evil heartmind" in Wang Yangming's "four-sentence doctrine" which argued extensively by scholars in the middle and late Ming Dynasties, and then the discussion leads to Liu Zongzhou's view on human nature. Liu Zongzhou put forward the theory of "nature is non-nature", he objects to scholars' groundless discussion of nature, and believes that nature is "the nature of the heartmind" which means nature is the essence of heartmind, it carries out in the moral activities of heartmind. Secondly, Liu Zongzhou also opposes the view that nature can be divided into the temperament and the moral nature. He believes that moral is the nature of temperament. Through eliminating the independence of nature, Liu Zongzhou completely excludes the problem of daydreaming about the nature by scholars. The second section focuses on Liu Zongzhou's views on the structure of heartmind and its activity mechanism. Liu Zongzhou thinks that heart is the movement of Qi. When Qi moves, it will express as four kinds of Qi: joy, anger, sadness and joy. The four kinds of Qi which move all time will become humanity, justice, propriety wisdom and seven emotions. Heartmind is a polyhedron that runs through Qi, doctrine (nature) and matter. As far as its activities are concerned, heartmind is a void body with reaction ability. It will be reflected in the activities as Si, Lu, Xiang, Shi, Nian, Yi, etc. Liu Zongzhou puts emphasis on the difference of Yi and Nian. He thought that Yi is the host of heartmind instead of Nian; Yi always exists while Nian non-exists sometime; Yi lives in the heartmind while Nian comes from the activity of heartmind; Liu Zongzhou's concept of Nian is equal to other scholars' notion of Yi. According to Liu Zongzhou's understanding of mind-nature, people can only realize and experience the nature from the activity of heartmind. Liu Zongzhou’s mind-nature theory is the theoretical foundation of his whole humanities thought.

The second chapter discusses Liu Zongzhou's viewpoint on Chengyi and Shendu. This problem is based on the mind-nature theory in the previous chapter, and lays a foundation for practice thoughts in the following chapter. On the question of Chengyi, Liu Zongzhou uses like and dislike which is the most primitive instinct of human to refers to Yi. Modern scholars often ignore the meaning brought by original and intentional trait of Yi referred by Liu Zongzhou. Liu Zongzhou believes, the intention of like good and dislike evil which appears from Yi makes human show some kinds of moral intention and activity according to the specific situation when they deal with the outside experience world. Yi is the internal basis and dynamic of moral activity. Thus, Yi is not only the source of virtue, but also has the ability of likes and dislikes. It could include the both aspects of ontology and Kungfu. Based on the above views, he indicates that Chengyi is the only and the complete purpose of "Da Xue", besides, Gezhi provides services for Chengyi. The second sector demonstrates Liu Zongzhou's Shendu thought from the angle of Duiyue. Liu Zongzhou not only disapproved of Zhu Xi’s view of explaining Shendu as external conducts, but also kept a wary eye on the drawback caused by Wang Yangming's argument of interpreting Du to consciences. On the one hand, he takes the human nature into the heartmind, which not only completes the value determination of Du, but also makes Du have the ability of activity. On the other hand, he believes Shen includes the meaning of introspecting consciousness, cultivating conscience, keeping straightforward. By this explanation, he constructed the internal structure of Shendu, made Shen and Du become a relationship of two-way loop and mutual achievement. Scholars often ignore the relationship between "Duiyue" and "Shen" in Liu Zongzhou's thought, as well as its significance of Kungfu Theory. Duiyue is the process of removing the mask of habituation, restoring the "true face" of Du and manifesting the activity of Du. In Liu Zongzhou's thought, Yi and Du both have ontological meaning, but Yi focuses on the activities of the heart, while Du focuses on the perspective of nature. Liu Zongzhou's theory of Shendu and Chengyi is the manifestation of his mind-nature theory at the level of Gongfu.

The third chapter expounds the practical methods of being a human in Liu Zongzhou's humanities thought from two aspects: the three junctures of being sage and the way of repentance. This chapter is mainly based on the two texts of " the Three Junctures of Being a Sage" and "the Way of Being a Sage". "The Three Junctures of Being a Sage " points out the three tenets of practice: firstly, practice is "Learning for Oneself" with the ultimate goal of self-realization. Secondly, the theory of Shendu and Chengyi is embodied in respectfulness, respectfulness leads to sincerity and sincerity leads to the showing of nature. Thirdly, the significance of practice is to make people realize themselves in the way of enlightenment which is the result from respectfulness. " The Way of Being a Sage " taking Shendu theory as the soul, it analyzes six kinds of human faults. Six faults are rooted in slight faults, forming a progressive structure of Russian nesting doll style. To correct six faults, " the Way of Being a Sage " puts forward the reform plan of "six lessons", and repentance is the most fundamental way to reform.

The fourth chapter discusses Liu Zongzhou's view on life and death and the theory of all in one, showing the ultimate concern and realm of individuals after becoming "human". On the issue of life and death. Liu Zongzhou believes that ordinary people always deal with others in a private way, resulting in the isolation between self and others. Life and death become the cage of life, and fear becomes the basic emotional state. Through the Kungfu of Shendu, he will overcome selfishness by respectfulness, so that he is fearless, and then goes out of life and death, and returns to the true state of existence. In the state of true existence, individuals not only individualize himself but also integrate with things. He can go along with all things with the feeling of justice and peace. He can realize the identity of life and death while he puts death in life, and finally inhabits in the eternal home of Tao. Liu Zongzhou's theory of all in one includes ontology, Kungfu theory and realm theory. The endless benevolence of life is the ontological basis of the theory of all in one. Liu Zongzhou especially emphasized that the only way one reaches the realm of all in one is practice, and opposed the idea that you can be one with all things once you find noumenon.

Liu Zongzhou's humanities thought gives a complete answer to the question of "learning to be human". This has played a significant role in changing the general mood of scholar and the academic atmosphere at that time, and even affected the development trend of Qing Dynasty.