The main purpose of this paper is to investigate various notions of empirical equivalence in relation to the two main arguments for realism in the philosophy of science, namely the no-miracles argument and the indispensability argument. According to realism, one should believe in the existence of the theoretical entities (such as numbers and electrons) postulated by empirically adequate theories. According to the no-miracles argument, one should do so because truth is the the best explanation of empirical adequacy. According to the indispensability argument, one should do so because the theoretical terms employed in the formulation of an empirically adequate theory are practically indispensable for the formulation of its empirical content. The no-miracles argument might be refuted if one can establish an underdetermination thesis to the effect that every theory has empirically equivalent rivals that are incompatible with each other. Insofar as truth cannot explain the empirical adequacy of two incompatible theories, there is an obvious conflict between the underdetermination thesis and the no-miracles argument. I show that, under certain assumptions, some but not all notions of empirical equivalence support the underdetermination thesis. The indispensability argument might be refuted if one can establish a dispensability thesis to the effect that, for any theory with a practical formulation (e.g. for any axiomatizable theory), there is an empirically equivalent theory with a practical formulation in purely empirical terms. I show that (using axiomatizability as the measure of practicality) some but not all notions of empirical equivalence support this thesis.

中文翻译：

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现实主义和经验等价

本文的主要目的是研究与科学哲学中现实主义的两个主要论点有关的经验等价的各种概念，即没有奇迹的论点和不可或缺的论点。根据实在论，人们应该相信由经验充分的理论所假设的理论实体（例如数字和电子）的存在。根据无奇迹论点，人们应该这样做，因为真理是对经验充分性的最好解释。根据不可或缺的论点，人们应该这样做，因为在形成经验充分的理论时所使用的理论术语对于其经验内容的形成实际上是必不可少的。如果人们可以建立一个不确定性命题，大意是每个理论都有经验上等价的彼此不相容的竞争对手，那么无奇迹论点可能会被驳斥。就真理不能解释两个互不相容的理论的经验充分性而言，不确定性论题与无奇迹论点之间存在明显的冲突。我表明，在某些假设下，一些但不是所有的经验等价概念都支持欠定论。如果一个人可以建立一个可有可无的论点，即对于任何具有实际公式的理论（例如对于任何公理化理论），都存在一个具有纯经验术语的实际公式的经验等价理论，那么必然性论证可能会被驳斥。