我们生活在一个价值碎片化的时代，当代哲学家尝试用不同的方法寻求道德客观性，但都陷入理论困境之中。这说明伦理生活包含有无法合理解决的价值冲突是我们必须接受的事实，而不是为了理论的一致性而应该清除的东西，从而要求伦理学调整对自己的本性与限度的理解，重新思考伦理学与形而上学以及与政治哲学的边界与关系问题。

Value Pluralism makes human being’s morality life to have been in hot water. We need to resist the motivism and establish a stable rational foundation for the moral standards. According to the fact and value relation’s different view，we may divide the method that contemporary moral philosophers devote to solve this problem into three ways：consensus，intermediary，transcendency. The above common grounds base the Post-metaphysical horizon to solve the moral objectivity problem that provides a very good direction of advance for us. But these theories actually also have respective knottiness. Value Pluralism means that there are Value Conflicts that are difficult to seek a fair and reasonable solution in our ethical life. This is a fact we must accept，but not something we can get rid of for consistency of theory. It requires ethics even philosophy adjusts the comprehension of its nature and limitation.This book tries to found for exploring the relationship between ethics and metaphysics through the distinction between metaphysic of knowledge and metaphysic of morals，and the distinction between the highest good and special good. On the one hand，the highest good of metaphysics plays a role of performance as a reminder and wake-up call. Only when any special goods attempts to arrogate，it will be apparent to warn of the cross-border of the special goods. Its existence is not awareness when it does not be touched. In other words，the highest good of metaphysics is the absolute form that cannot be recognized or understood. All we can know about it is that anything we called our understanding of it is false. Second，there is no positive proof. The highest good of metaphysics which is a concept of pure form cannot be said or be proved. All positive proof about it must be informative. In this sense，ethics can only be the sense of the source rather than common sense. Source ethics does not institute rules for human behavior，but rather to remind people to face the real situation that public sphere and private areas are entirely different. It also maintains that the subject will incline to be good. The public sphere requires universally valid guidelines，which only political system，but cannot be special good. The vital principle in the public sphere is“Righteous Priori to Goodness”；in the private sector，there is no absolute rule，individuals have supreme jurisdiction. In order to prevent this abuse of power，we should develop the moral judgment.Key words：Ethics；Political Philosophy；Metaphysics；Boundary