## Published & Forthcoming Papers

**Impossible Worlds and Partial Belief**

** |***Forthcoming in Synthese*

The open-access published version is also available at https://link.springer.com/article/10.1007/s11229-017-1604-8

**Abstract:**One response to the problems of logical omniscience is to extend the space of possible worlds to include impossible worlds. It is natural to think that essentially the same strategy can be applied to standard probabilistic models of partial belief, for which parallel problems also arise. In this paper, I note a difficulty with the inclusion of impossible worlds into probabilistic models. With only very weak assumptions about the space of worlds, most of the propositions which can be constructed from possible and impossible worlds are in an important sense

*inexpressible*; whereas the probabilistic model seems committed to saying that agents in general have at least as many attitudes towards inexpressible propositions as they do towards expressible propositions. If it is reasonable to think that our attitudes are generally expressible, then a model with such commitments looks problematic.

**A Representation Theorem for Frequently Irrational Agents |**

**2017,**

*Journal of Philosophical Logic 46 (5): 467-506*

The published version is available at http://link.springer.com/article/10.1007%2Fs10992-016-9408-8

**Abstract:**The standard representation theorem for expected utility theory tells us that if a subject's preferences conform to certain axioms, then she can be represented as maximising her expected utility given a particular set of credences and utilities--and, moreover, that having those credences and utilities is the

*only*way that she could be maximising her expected utility (given her preferences). However, the kinds of agents these theorems seem apt to tell us anything about are highly idealised, being (amongst other things) always probabilistically coherent with infinitely precise degrees of belief and full knowledge of all

*a priori*truths. Ordinary subjects do not look very rational when compared to the kinds of agents usually talked about in decision theory. In this paper, I will develop an expected utility representation theorem aimed at the representation of those who are neither probabilistically coherent, logically omniscient, nor expected utility maximisers across the board--that is, agents who are

*frequently irrational*. The agents in question may be deductively fallible, have incoherent credences, limited representational capacities, and fail to maximise expected utility for all but a limited class of gambles.

**Probabilism, Representation Theorems, and Whether Deliberation Crowds out Prediction |**2017,

*Erkenntnis 82 (2): 379-399*

The published version is available at http://dx.doi.org/DOI:10.1007/s10670-016-9824-8

**Abstract:**Decision-theoretic representation theorems have been developed and appealed to in the service of two important philosophical projects: (i) in attempts to characterise credences in terms of preferences, and (ii) in arguments for probabilism. Theorems developed within the formal framework that Savage developed have played an especially prominent role here. I argue that the use of these 'Savagean' theorems create significant difficulties for both projects, but particularly the latter. The origin of the problem directly relates to the question of whether we can have credences regarding acts currently under consideration and the consequences which depend on those acts; I argue that such credences are possible. Furthermore, I argue that attempts to use Jeffrey's non-Savagean theorem (and similar theorems) in the service of these two projects may not fare much better.

**Ramsey Without Ethical Neutrality |**2017,

*Mind 126 (501): 1-51*

The published version is available at http://mind.oxfordjournals.org/content/early/2016/10/13/mind.fzv180.full.pdf?keytype=ref&ijkey=y2Dzzq2PeqPKP1v

**Abstract:**Frank Ramsey’s ‘Truth and Probability’ sketches a proposal for the empirical measurement of credences, along with a corresponding set of axioms for a (somewhat incomplete) representation theorem intended to characterize the preference conditions under which this measurement process is applicable. There are several features of Ramsey’s formal system which make it attractive and worth developing. However, in specifying his measurement process and his axioms, Ramsey introduces the notion of an ethically neutral proposition, the assumed existence of which plays a key role throughout Ramsey’s system. A number of later representation theorems have also appealed to ethically neutral propositions. The notion of ethical neutrality has often been called into question—in fact, there seem to be good reasons to suppose that no ethically neutral propositions exist. In this paper, I present several new, Ramsey-inspired representation theorems that avoid any appeal to ethical neutrality. These theorems preserve the benefits of Ramsey’s system, without paying the cost of ethical neutrality.

**Epistemic Two-Dimensionalism and Arguments from Epistemic Misclassification |**2013,

*Australasian Journal of Philosophy*

*91 (2): 375-389*(With Kelvin McQueen and Clas Weber).

The published version is available at http://www.tandfonline.com/doi/abs/10.1080/00048402.2012.693112

**Abstract:**Epistemic Two-Dimensional Semantics (E2D) claims that expressions have a counterfactual intension and an epistemic intension. Epistemic intensions reflect cognitive significance such that sentences with necessary epistemic intensions are

*a priori*. We defend E2D against an influential line of criticism:

*arguments from epistemic misclassification*. We focus in particular on the arguments of Speaks [2010] and Schroeter [2005]. Such arguments conclude that E2D is mistaken from (i) the claim that E2D is committed to classifying certain sentences as

*a priori*and (ii) the claim that such sentences are

*a posteriori*. We aim to show that these arguments are unsuccessful as (i) and (ii) undercut each other. One must distinguish the general framework of E2D from a specific

*implementation*of it. The framework is flexible enough to avoid commitment to the

*apriority*of any particular sentence; only specific implementations are so committed. Arguments from epistemic misclassification are therefore better understood as arguments for favouring one implementation of E2D over another, rather than as refutations of E2D.

## Works in Progress

**Unawareness and Implicit Belief: Possible Worlds Models of Informational Content |**

*Under review*

**Abstract:**Possible worlds models of belief have difficulties accounting for

*unawareness*, the inability an agent may have to entertain (and hence believe) certain propositions. Accommodating the possibility of unawareness is important for adequately modelling epistemic states, and representing the informational content to which agents have access given their explicit beliefs. In this paper, I use neighbourhood structures to develop an original multi-agent model of explicit belief, awareness, and informational content, along with an associated sound and complete axiom system. I also defend the model against the seminal impossibility result of Dekel et al. (1998), according to which three intuitive conditions preclude non-trivial unawareness on any `standard' model of knowledge or belief. I argue that at least one of these conditions is implausible when applied to a model of belief. The plausibility of the two others rests on further questions regarding the scope and granularity of mental content; however, I also show that it's possible to strengthen these conditions while retaining non-trivial unawareness.

**Comparativism and the Measurement of Partial Belief |**

*Under Revise & Resubmit*

**Abstract:**Comparativism is the view that comparative beliefs (e.g., believing p to be more likely than q) are more fundamental than partial beliefs (e.g., believing p to some degree x). In this paper, I first provide an account of how comparativism can make sense of quantitative comparisons (e.g., believing p twice as much as q), which generalises and improves upon the standard comparativist approach. This is achieved by means of a simple 'Ramseyan' representation theorem, with axioms demonstratively weaker than those to which comparativists usually appeal. I then provide a number of arguments against comparativism. Ultimately, there are too many things that we ought to be able to say about partial beliefs that we cannot say under any version of comparativism. Moreover, there are alternative ways to account for the measurement of belief that need not face the same limitations.

**Don't Stop Believing: On the Rationality of Inquiry into the Moral Error Theory |**

*With Jessica Isserow; draft available soon*

**Abstract:**It's natural to think that there's value to improving the accuracy of one's beliefs. If beliefs are a map by which we steer our efforts to bring the world in line with our preferences, then, all else being equal, we should want a more accurate map. However, the world could be structured so as to

*punish*learning with respect to certain topics; i.e., by coming to learn certain things, your situation as a whole may end up worse than it would have been otherwise. In this paper, we investigate whether the world is structured so as to punish learning specifically with respect to the moral error theory. We ask: If an ordinary human agent, with ordinary human preferences, had the option to learn whether the error theory is true, should she take it? We will argue that she should not.

**Recent Work on Decision Theory |**

*Invited, for Analysis Reviews*

**Abstract:**A survey of the major advances and debates in philosophical/normative decision theory over the past decade.

## Miscellaneous bits and pieces

**1.**

**Frank P. Ramsey: Partial Belief and Subjective Probability |**

*Stanford Encyclopedia co-authored entry*

**2.**

**'Ramseyfying' Probabilistic Comparativism |**

*Presented at F.E.W. 2018*

**3. Ramsey and the Ethically Neutral Proposition |**NatRep group: short unpublished exposition piece on Ramsey's representation theorem

**4. The Instability of Savage's Foundations: The Constant Acts Problem |**NatRep group: short unpublished exposition piece on Savage's representation theorem