Argumenta – Journal of Analytic Philosophy

The subjective probability of a subjunctive conditional is argued to be equal to the expected conditional credence in its consequent, given the truth of its antecedent, of an ‘expert’: someone who reasons faultlessly and who, at each point in time, is as fully informed about the state of the world as it is possible to be at that time.

Rothschild and Spectre (2018b) present a puzzle about knowledge, probability and conditionals. This paper analyzes the puzzle and argues that it is essentially two puzzles in one: a puzzle about knowledge and probability and a puzzle about probability and conditionals. As these two puzzles share a crucial feature, this paper ends with a discussion of the prospects of solving them in a unified way.

Once upon a time, some thought that indicative conditionals could be effectively analyzed as material conditionals. Later on, an alternative theoretical construct has prevailed and received wide acceptance, namely, the conditional probability of the consequent given the antecedent. Partly following critical remarks recently appeared in the literature, we suggest that evidential support—rather than conditional probability alone—is key to understand indicative conditionals. There have been motivated concerns that a theory of evidential conditionals (unlike their more traditional counterparts) cannot generate a sufficiently interesting logical system. Here, we will describe results dispelling…

A unified shared theory of conditionals does not still exist. Some theories seem suitable only for indicative but not for counterfactual ones (or vice versa), while others work well with simple conditionals but not compound ones. Ernest Adams’ approach—one of the most successful theories as far as indicative conditional are concerned—is based on a reformulation of Ramsey’s Test in a probabilistic thesis known as “The Equation”. While the so-called Lewis’ Triviality Results support Adams’ view that conditionals do not express genuine statements, the problem arises whether these results lead inevitably…

We illustrate the notions of compound and iterated conditionals introduced, in recent papers, as suitable conditional random quantities, in the framework of coherence. We motivate our definitions by examining some concrete examples. Our logical operations among conditional events satisfy the basic probabilistic properties valid for unconditional events. We show that some, intuitively acceptable, compound sentences on conditionals can be analyzed in a rigorous way in terms of suitable iterated conditionals. We discuss the Import-Export principle, which is not valid in our approach, by also examining the inference from a material…

The trivalent and functional theory of the truth of conditionals developed by Bruno de Finetti has recently gathered renewed interests, particularly from philosophical logic, psychology and linguistics. It is generally accepted that de Finetti introduced his theory in 1935. However, a reading of his first publications indicates an earlier conception of almost all his theory. We bring to light a manuscript and unknown writings, dating back to 1928 and 1932, detailing de Finetti’s theory. The two concepts of thesis and hypothesis are presented as a cornerstone on which logical connectives…

According to Lewis’ Triviality Results (LTR), conditionals cannot satisfy the equation (E) P(C if A) = P(C | A), except in trivial cases. Ernst Adams (1975), however, provided a probabilistic semantics for the so-called simple conditionals that also satisfies equation (E) and provides a probabilistic counterpart of logical consequence (called p-entailment). Adams’ probabilistic semantics is coextensive to Stalnaker-Thomason’s (1970) and Lewis’ (1973) semantics as far as simple conditionals are concerned. A theorem, proved in McGee 1981, shows that no truth-functional many-valued logic allows a relation of logical consequence coextensive with…

Agent-based models (ABMs) are one type of simulation model used in the context of the COVID-19 pandemic. In contrast to equation-based models, ABMs are algorithms that use individual agents and attribute changing characteristics to each one, multiple times during multiple iterations over time. This paper focuses on three philosophical aspects of ABMs as models of causal mechanisms, as generators of emergent phenomena, and as providers of explanation. Based on my discussion, I conclude that while ABMs cannot help much with causal inference, they can be viewed as etio-prognostic explanations of…

I present and analyze the case of COVID-19 modeling at the Public Health Agency of Sweden (FoHM) between February 2020 and May 2021. The analysis casts the case as a decision problem: mod­elers choose from a strategically prepared menu that model which they have reasons to believe will best serve their current purpose. Specifically, I argue that the model choice at FoHM concerned a trade-off between model-target similarity and model simplicity. Five reasons for choosing to engage in such a trade-off are discussed: lack of information, avoiding overfitting, avoiding fuzzy…