By definition, the implicit commitment of a formal theory \(\textrm{Th}\) consists of sentences that are independent of the axioms of \(\textrm{Th}\), but their acceptance is implicit in the acceptance of \(\textrm{Th}\). In Cieśliński (2017, 2018), the phenomenon of implicit commitments was studied from the epistemological perspective through the lenses of the formal theory of believability. The current paper provides a comprehensive proof-theoretic analysis of this approach and compares it to other main theories of implicit commitments. We argue that the formal results presented in the paper favour the believability theory over its main competitors. However, there is still a fly in the ointment. We argue that in its current formulation, the theory cannot deliver all the goods for which it was defined. In particular, being amenable to a generalised conservativeness argument, it does not support the view that the notion of truth is epistemically light. At the end of the paper, we discuss possible ways out of the problem.

根据定义，形式理论 \（\textrm{Th}\） 的隐含承诺由独立于 \（\textrm{Th}\） 公理的句子组成，但它们的接受是隐含在对 \（\textrm{Th}\） 的接受中。在 Cieśliński （2017， 2018） 中，通过形式可信度理论的镜头，从认识论的角度研究了隐含承诺现象。本文对这种方法进行了全面的证明理论分析，并将其与隐式承诺的其他主要理论进行了比较。我们认为，论文中呈现的正式结果有利于可信度理论而不是其主要竞争对手。然而，美中不足。我们认为，在其目前的表述中，该理论无法提供它所定义的所有商品。特别是，由于适合于普遍的保守性论点，它并不支持真理的概念在认识论上是轻的观点。在本文的最后，我们讨论了解决问题的可能方法。