우암 송시열은 조선의 주자학자이다. 그는 주자와 栗谷 李珥(1536-1584), 沙溪 金長生(1548-1631)을 존경하며, 조선에서 주자학을 확립하고자 노력하였다. 주자학에서 미발의 심체에 대한 본격적인 정론적 논의는 中和新說 이후에 이루어지고 있다. 주자는 중화신설에서 미발일 때 寂然不動한 心體가 자리 잡고 있고, 이 심체는 天命之性을 갖추고 있다고 보았다. 주자는 이 심체 측면을 虛靈이라 지칭하였다. 심체인 허령에 대한 우암의 핵심적 견해는 크게 세 가지로 요약할 수 있다. 첫째 허령은 리와 기가 합쳐진 것이 아니며 순수한 淸明한 기로 이루어졌다. 둘째, 심의 본체인 허령을 명덕으로 보아서는 안 된다. 셋째, 허령은 외부 사태에 감응하고 받아들일 수 있는 능력을 가진 活物이다. 우암은 虛靈의 虛를 事態에 직면하여 ‘능히 받아들일 수 있는 것(能受底)’․‘받아들일 수 있는 근거(所以能受)’라는 의미로 해석하고, 靈을 사태에 ‘능히 感應할 수 있는 것(能感底)’․‘감응 할 수 있는 근거(所以能感)’라는 뜻으로 정의하였다. 그리고 이러한 가능태로서의 허령은, 사태에 직면하여 지각작용으로서 드러나게 된다고 보았다. 우암은 未發에서 寂然不動한 가능태로 잠재되어 있던 體의 측면인 허령이, 已發에서 받아들이고 감응하는 用의 측면인 지각작용으로 드러나게 된다는 허령지각론을 전개하였다. 우암은 호락논변 이전의 인물이다. 우암의 미발 심체인 허령에 대한 견해는, 호론과 낙론의 허령론으로 분화되기 이전의 논의로서, 호락론자들에게서 보이는 바와 같은 정도의 면밀한 분석이 이루어지지 않았다. 우암의 견해는 낙론의 대표적 인물인 巍巖 李柬(1677-1727)이나 호론의 대표적 인물인 南塘 韓元震(1682-1751)과 차이가 있다.

Song Si-yeol was one of scholars who were filial to the science of Zhu Xi in Yi dynasty. He respected Zhu Xi, Lee Yi and Kim Jang-seng, and tired to establish the science of Zhu Xi in Yi dynasty. In the science of Zhu Xi, an established discussion of the not-yet-activating substance of heart-mind was made after the new doctrine of equilibrium and harmony. Zhu Xi argued that, when it did not activate yet, there was a substance of calmness and not-moving in the heart-mind and had the human nature of Heavenly Mandate. He called it the spirit of emptiness. Song Si-yeol's view of the spirit of emptiness, namely, the substance of heart-mind can be summarized into three parts: Firstly, it is not a unification of principle and vital force, but is composed of the vital force of pure clearance. Secondly, as the substance of heart-mind, it is not regarded as the brightening virtue. Thirdly, it is a living thing whose ability responds to and acceptable for the external situations. He understood the word emptiness as what or the ground that was acceptable for situations of things, and defined the word spirit as what or the ground that could respond to situations of things. And he regarded the spirit of emptiness, which was an ability of acceptability and response, as having a function of perception for situations of things. He argued the doctrine of perceiving the spirit of emptiness that the spirit of emptiness, which was the substance of having a possibility of calmness and not-moving in non-activation, revealed as the function of being acceptable and responding in activation. He lived before beginning the debate of Ho-lak. His view of the spirit of emptiness, namely, the substance of heart-mind appeared before it was divided into the doctrine of Ho and that of Lak, and so it did not make a precise analysis as the scholars of Ho and Lak did. It was different from Lee Gan's, as a representative for the doctrine of Lak, and Han Won-jin's, as a representative for the doctrine of Ho.

Song Si-yeol was one of scholars who were filial to the science of Zhu Xi in Yi dynasty. He respected Zhu Xi, Lee Yi and Kim Jang-seng, and tired to establish the science of Zhu Xi in Yi dynasty. In the science of Zhu Xi, an established discussion of the not-yet-activating substance of heart-mind was made after the new doctrine of equilibrium and harmony. Zhu Xi argued that, when it did not activate yet, there was a substance of calmness and not-moving in the heart-mind and had the human nature of Heavenly Mandate. He called it the spirit of emptiness. Song Si-yeol's view of the spirit of emptiness, namely, the substance of heart-mind can be summarized into three parts: Firstly, it is not a unification of principle and vital force, but is composed of the vital force of pure clearance. Secondly, as the substance of heart-mind, it is not regarded as the brightening virtue. Thirdly, it is a living thing whose ability responds to and acceptable for the external situations. He understood the word emptiness as what or the ground that was acceptable for situations of things, and defined the word spirit as what or the ground that could respond to situations of things. And he regarded the spirit of emptiness, which was an ability of acceptability and response, as having a function of perception for situations of things. He argued the doctrine of perceiving the spirit of emptiness that the spirit of emptiness, which was the substance of having a possibility of calmness and not-moving in non-activation, revealed as the function of being acceptable and responding in activation. He lived before beginning the debate of Ho-lak. His view of the spirit of emptiness, namely, the substance of heart-mind appeared before it was divided into the doctrine of Ho and that of Lak, and so it did not make a precise analysis as the scholars of Ho and Lak did. It was different from Lee Gan's, as a representative for the doctrine of Lak, and Han Won-jin's, as a representative for the doctrine of Ho.

Song Si-yeol, the substance of heart-mind, the spirit of emptiness, the doctrine of Ho, the doctrine of Lak, brightening virtue