Evidence and Objective Bayesian Epistemology

主观贝叶斯认识论目前被广泛认为是科学哲学中的证据推理范式，以及支撑决策制定的主导帐户的理性信念程度，以及我们的许多统计方法。客观(！)贝叶斯认识论正在作为一种挑战主观解释的另类认识论出现。客观贝叶斯认为理性的信任度是由代理人的证据决定的，而主观贝叶斯则认为给定代理人的证据存在一个合理的信任度范围。我们迫切需要确定我们应该采用哪种贝叶斯认识论。这个项目旨在加强客观方法的理由。主观贝叶斯认识论中的证据推理基于两个长期相互关联的部分：它基于期望效用最大化，这是通过条件化更新信念来实现的。人们会争辩说，这些部分面临着迄今未得到充分认识的困难。目前，客观贝叶斯认识论中的证据推理缺乏坚实的证据推理基础，也缺乏证据推理实现的框架。没有这些基础和这样的实现目标，贝叶斯认识论就不能站在主观方法的立场上。因此，这个项目将为客观贝叶斯认识论中的证据推理奠定基础。此外，客观方法将为证据推理提供一个全面的框架。这项研究将揭示形式认识论中的核心争论，即主观方法和客观方法中的哪一个更好地表征了信仰的规范。这场辩论的结果与决策、科学和日常生活中的理性决策高度相关，因为这两种方法通常将不同的行为列为理性。这一结果还与统计学和人工智能有关，在统计学和人工智能领域，贝叶斯原则被广泛使用，但对于主观贝叶斯原则还是客观贝叶斯原则是最好的，各方几乎没有达成一致。

Subjective Bayesian epistemology is currently widely perceived to be the paradigm of evidential reasoning in the philosophy of science and of rational degrees of belief underpinning the dominant account of decision making, as well as many of our statistical methods. Objective(!) Bayesian epistemology is emerging as an alternative epistemology challenging the subjective account. Objective Bayesians hold that rational degrees of belief are determined by the agent's evidence while subjective Bayesians claim that there is a range of rational degrees of belief given an agent's evidence. We urgently need to determine which Bayesian epistemology we should employ. This project aims to strengthen the case for the objective approach.Evidential reasoning in subjective Bayesian epistemology is based on two long-standing interconnected parts: it is grounded in expected utility maximisation which is implemented by updating beliefs via conditionalisation. It will be argued that these parts face so-far under-appreciated difficulties. Currently, evidential reasoning in objective Bayesian epistemology is lacking solid foundations for evidential reasoning to stand upon and is also lacking a framework for an implementation of evidential reasoning. Without these foundations and such an implementation objective Bayesian epistemology cannot aspire to stand up to the subjective approach.This project will hence develop foundations for evidential reasoning in objective Bayesian epistemology. Furthermore, the objective approach will be supplied with a comprehensive framework for evidential reasoning. It will be argued that the provided foundations and the developed implementation are superior to those of the subjective approach in key aspects and thus strengthen the case for the objective approach.This research will inform a core debate within formal epistemology, namely the question of whether the subjective or the objective approach better characterises the norms governing belief. The outcome of this debate is highly relevant to rational decision making in policy-making, science and daily life since the two approaches single out different actions as rational, in general. The outcome is furthermore relevant to statistics and artificial intelligence, where Bayesian principles are widely used and where there is little agreement as to whether subjective or objective Bayesian principles are best.