法律推理與法律的無可決性：一個對「無可決性論戰」的批判性反思

法律的無可決性（the indeterminacy of law）是一個法理學上的經典論題，　其大致上指涉「法律不能就法律問題提供一個唯一的正確答案」這樣的性質。人們對法律無可決性有所爭論，通常是圍繞於「裁判的不一致性」──即相同的法律規定，卻在不同的實務運作中產生迥異、甚至矛盾之裁判結論的現象而展開。不過，本文認為法律無可決性爭論所涉及的問題其實更為深層，其牽涉到的是法理學中「法律推理理論」（theory of legal reasoning）這個次領域的討論範疇。有鑒於此，本文將首先就何謂法律推理理論做出一番定位與說明。　　然而，本文認為法律無可決性的爭論，仍沒有被法律人足夠認真地對待。那麼，問題出在哪裡呢？筆者認為，除了法律人對法律無可決性爭論的前提，一直欠缺恰當的定位與說明之外，對本文而言更為關鍵的，是法律人實際上對法律無可決性普遍持有的，一種既非「形式」卻也似非全然「現實」（real）的複雜折衷式立場。而本文最核心的問題意識，便是希望能為這個未曾被明說的「黑盒子」，提供一些被打開後能提供合理解釋的理論可能性。　　就此，本文選擇英美法理學的無可決性論戰（Indeterminacy debate）作為主要參照的思想資源。在無可決性論戰的典型敘事中，德沃金的唯一正解命題與批判法學的基進懷疑論，無疑是最為標識性且針鋒相對的兩大代表性陣營。透過對這兩大理論陣營的重新考察，本文嘗試釐清雙方之間的異與同，並藉由對此典型敘事的檢討，總結出一套本文認為更適當、更好用的討論架構，進而在兩者之間發掘更多的可能性。　　本文的結論，是認為對法律無可決性的爭論，最終會導向的是對法律本質（the nature of law）的幾種理解，而「法律人」（lawyer, jurist）對此的立場，不僅很大程度地影響了我們設想法律問題的基本立場，也會導向我們對於何謂法治（rule of law）截然不同的想像。因此，認真對待自己對法律無可決性爭論的答案，將是我們在尋求相互理解的道路上，最需要持續做出反思之處。

關鍵字

法律推理；法律推理理論；法律的無可決性；無可決性論戰；哈特；德沃金；批判法學；預測理論

並列摘要

The indeterminacy of law is a classic topic of jurisprudence, which generally refers to the nature of that “law can not provide a unique correct answer to legal questions.” People have disputes about the legal indeterminacy, usually around the "inconsistency of adjudication"--that is, the phenomenon that the same legal norms produce different or even contradictory conclusions in different cases. However, this thesis believes that the issues that involved in the debate of legal indeterminacy are actually much deeper, which involves the discussion of the jurisprudence sub-field called “Theory of Legal Reasoning “. Therefore, this thesis will first make a positioning and explanation on what is the “Theory of Legal Reasoning ". However, this thesis argues that “lawyers” have not taken the debate of legal indeterminacy seriously enough. So, where is the problem? This thesis believes that in addition to the premise that lawyers argue about legal indeterminacy, there has been a lack of proper positioning and explanation. The more critical part for this thesis is that lawyers actually generally hold the complex position of the indeterminacy of the law--a complex position that is neither "FORMAL" but nor purely "REAL". Therefore, the core problematic of this thesis is to provide some theoretical possibilities that can provide reasonable explanations for this unexplained "black box". In this regard, this thesis chooses the Indeterminacy debate of Anglo-American jurisprudence as the main source of reference. In the classic narrative of this debate, Ronald Dworkin’s “The-Only-Right-Answer" argument and the radical skepticism of the Critical Legal Studies are undoubtedly the two most typical and even conflicting camps of legal reasoning theories. Through a re-examination of these two theoretical camps, this thesis attempts to clarify the similarities and differences between the two parties, and through the review of the classic narrative, sums up a set of discussion frameworks that this thesis believes is more appropriate and more useful, and then explore more possibilities between the two. The conclusion of this thesis is that the debate of legal indeterminacy will eventually lead to several understandings of “the nature of law". The position of the "lawyers” on this not only greatly affected our basic position on legal issues, but also led to a completely different version of how the “Rule of Law" ought to be. Therefore, taking seriously our answers to the legal indeterminacy debate will be where we need to continue to rethink on the road to mutual understanding.