客体小a是拉康的一个谜,其定义多样并复杂。它和现实世界相关,又在现实世界之外。本文总结了这个概念的主要理论起源、澄清了其定义的多样性和歧义性。在此基础上,笔者指出:其特征是一种特殊的非因果的逻辑,即“自身差异性”。这个特征揭示了主体欲望的秘密,其独特性能更好地被形式语言所刻画。 The small object a is Lacan’s mystery, its definition is diverse and complex. It is related to the real world and again outside the real world. This article summarizes the main theoretical origins of this concept and clarifies the diversity and ambiguity of its definition. On this basis, the author points out: Its characteristic is a kind of special non-causal logic, that is, “self-difference”. This feature reveals the secrets of the subject’s desires, whose distinctiveness is better characterized by formal language.