论物理学中的类比方法 以汤姆森和麦克斯韦为例

On the Analogy Method in Physics:in the Cases of Thomson and Maxwell

类比方法是亚里士多德提出的逻辑学方法之一,但这一方法的严格性,乃至它是否可以被算作一种逻辑方法,在亚里士多德之后却一直饱受质疑。正因为如此,19世纪英国物理学家汤姆森和麦克斯韦将类比方法引入电磁学研究时曾受到严重的质疑。20世纪中叶,玛丽·海斯等西方哲学家试图将类比方法纳入到现代逻辑学体系中,并以此解释汤姆森和麦克斯韦的工作。但他们的出发点仍然是将类比置于一个基于事物间偶然联系的启发工具的地位上,这既不足以为物理类比方法的正当性提供辩护,也无法解释这种方法在物理学中表现出的广泛的适用性和有效性。本文将从重构汤姆森和麦克斯韦引入类比方法的过程入手,分析他们使用类比论证的依据。本文将论证,物理学中的类比方法是一种严格的科学方法,应明确地区别于一般逻辑学以及大众话语中所说的"类比"。这种方法的严格性来自于它所依据的唯一的类比基础,即不同物理现象的数学形式间的相似性。进而以此为基础浅论麦克斯韦的"数学分类"思想。

Analogy is one of Aristotle＇s logic methods. It, however, is still a question that whether this method is strict, and even that whether analogy is a logic method. Since this is so, William Thomson and James Clerk Maxwell were heckled when they introduced the analo research in the 19th century. In the middle gY of method into the electromagnetics the 20th century, some philosophers tried to bring the analogy method into the system of the modern logic, and to explain the achievements of Thomson and Maxwell on the basis of this system. Their explanations, however, is not only inadequate to justify the analogy method, but also helpless to explain the broad applicability of this method in physics. This article will restructure the approach by which Thomson and Maxwell introduced the analogy method, and analyze the reasons that they appealed to this method. It will be demonstrated that the analogy method in physics is a strict scientific method, and is definitely different with the so-called ＂analogy＂ which is familiar in the words of logic or ordinary language; the stringency of this method comes from the unique basis on which a physical analogy is built, that is the similarity between the mathematical forms of the different physical phenomena. On this basis, Maxwell＇s idea of ＂Mathematical Classification＂ will be discussed.