本文首先指出 Larenz 確定法律效果三段論在邏輯上的缺陷，再嘗試運用現代邏輯來分析涵攝的邏輯結構。法學三段論只能代表法律適用的簡單形式，當法規範的構成要件與具體案例事實存在裂縫時，法學三段論即面臨侷限，此時必須透過涵攝將構成要件與具體的案件事實連結起來。若要精確的表達涵攝的邏輯結構，必須將法學三段論擴展為涵攝的演繹模式。涵攝的演繹模式代表了法律論證之內部證立的複雜形式，而演繹模式中前提的正確性或真實性則屬於外部證立的對象。涵攝的演繹模式除了要求具體的法律效果必須從論證的前提透過邏輯推導而出之外，尚必須滿足一致性的要求、可普遍化的要求以及說理完備性的要求等說理規則，這些說理規則表達了對法律論證最低限度的理性要求。本文最後並對Larenz的主張「類型不能以涵攝的方式被適用」提出批判性的檢討。

Beginning with the logical deficiencies in Larenz's "Syllogismus der Rechtsfolgebestimmung", this paper tries to use the modern symbol logic to analyze the formal structure of subsumption. The so called "Legal Syllogism" stands only for the simple form of the application of the law and is faced with its limitation when a "gap" (Kluf) exists between the description of a concrete case and the condition of a norm. This gap is to be bridged by the subsumption. In order to give a precise account of the logical structure of subsumption, the legal syllogism should be extended to the deductive scheme of subsumption. The deductive scheme represents the complex form of internal justification. The truth or rightness of the premises used in the deductive scheme is the object of external justification. The internal justification requires not only the logical deduction of the legal consequence from a set of premises, the premises in the deductive scheme, for their part, must also satisfy the requirements of consistency, universalizability, and justificatory completeness. All these requirements constitute the minimal demands for a rational legal justification. The last part is a critical assessment of Larenz's theory of Typus.