本文主要內容係對大乘中觀學派自性空概念之本真意義的澄清。中觀學派的性空論在現代的流俗解釋中，常被粗泛地理解為一種反實體論，一種相對主義，或是一種精緻的概念辨證法，此類流俗解釋的一個共同原因在於完全誤解了中觀之空性所直接針對的自性概念。本文依據中觀學派文本所直接提供的材料，通過對中觀學派之「空」、「自性」、「緣起性」、「不離性」等核心概念的深入分析，表明性空論所涉及的自性概念在其嚴格意義上實指「自身同一性」，因而性空論實為一種非同一性理論，其核心宗旨乃是對「同一性」概念的徹底解構，其命題形式採用了一種與「同一律」（A即A）正相反對的形式：A非A，不妨稱之為一種「非同一律」。中觀學派的核心概念「自性空」，乃是對「緣起性」這一概念所作的分析性結論，這一點對於整個中觀學派而言具有決定性的意義，因為它保證了「自性空」的純演繹性質，從而也就保證了其必然真理的屬性。性空論對同一性的解構不是基於邏輯學的角度而基於存在論的立場，並以二諦論解釋了邏輯學的「同一律」與存在論的「非同一律」之間的矛盾。作為一種唯現象主義的和內在關係論的存在論，中觀性空論與現象學和存在主義不無可相比較之處。

This article seeks to clarify the true significance of the Madhyamaka school’s concept of emptiness of self-nature. This theory of empty nature, in contemporary popular understanding, is often understood as being anti-ontological, or as a type of relativism, or a sophisticated dialectic. A commonality in these interpretations is that they all misunderstand the self-nature toward which the Madhyamaka’s emptiness is directed. This paper, relying on Madhyamaka texts, presents an in-depth analysis of the core concepts of “empty,” “self-nature,” “dependent origination,” and “identity with nature,” showing that this concept of self-nature, strictly defined, refers to “self-identity.” Therefore, the theory of emptiness serves as a type of non-identity theory. Its core message is directed at a complete deconstruction of identity, and its proposition is opposite the law of identity (A is A), thus expressed in the form of non-identity (A is not A). As a core concept of the Madhyamaka school, emptiness of nature is directed at dependent origination. This point, for the Madhyamaka school, is of crucial importance, because it guarantees the purely deductive nature of the “emptiness of nature”; from this, its quality of necessary truth is also guaranteed. The deconstruction of identity in the theory of emptiness of nature is not based on logic, but is based on ontology, and uses the two truths to interpret the contradiction between a logical “law of identity,” and an ontological “law of non-identity.” As an ontology of phenomenology and internal relations theory, Madhyamaka’s theory of emptiness of nature bears comparison with phenomenology and existentialism.