Hi, I'm Mike Deigan, a philosophy PhD candidate at Yale with broad interests.

Starting Fall 2020 I will be a Mellon Foundation Postdotoral Fellow in Philosophy at Rutgers.

My dissertation is on the epistemology of concepts. I want to know what, given one's evidence, one should be able to think.

Besides this, I mostly work on language and ethics, trying to answer questions like “What does the word ‘a’ mean?” and “How should we live?”.

Here's my cv.

Below are some papers I've written, as well as slides and handouts for talks.

Comments/questions are welcome!



    under review

  • Having a Concept Has a Cost
    // email me for a draft

    I argue that concept possession has an epistemic opportunity cost, even for highly idealized agents.

  • Stupefying
    // email me for a draft

    S stupefies A when A accepts S's assertion without understanding it.

    I argue stupefying is an important means both for good (cooperative, jointly rational inquiry) and bad (manipulation of others against their own interests), in ways that current models of conversation do not account for.

  • Offsetting
    // email me for a draft

    I argue that to make sense of the permissibility of offsetting, we need to replace the standard deontological constraint against harm with one against unoffset harm increases.

  • Value Priority Monism
    // email me for a draft

    It is usually assumed without question that the final value of a world is derived from the value of its parts. I argue its worth considering a priority monism about value akin to the ontological priority monism defended by Schaffer (2010).

  • forthcoming

  • A Plea for Inexact Truthmaking
    Linguistics and Philosophy
    // PAPER (pdf, link to journal version)

    Kit Fine (2017) distinguishes between inexact and exact truthmaking. He argues that the former can be defined from the latter, but not vice versa, so truthmaker semanticists should treat the exact variety of truthmaking as primitive. I argue that this is mistaken. We can define exact truthmaking in terms of inexact truthmaking and we can't define inexact truthmaking in terms of exact truthmaking. I conclude that it's inexact truthmaking, rather than exact truthmaking, that truthmaker semanticists should treat as the primitive semantic relation.

  • 2018

  • Counterfactual Donkeys Don't Get High
    Proceedings of Sinn und Bedeutung 22
    // PAPER (pdf)

    I present data that suggest the universal entailments of counterfactual donkey sentences aren't as universal as some (Van Rooij (2005) and Walker and Romero (2015)) have claimed. I argue that this favors the strategy of attributing the universal entailments to a special property of the similarity ordering on worlds provided by some contexts, rather than to a semantically encoded sensitivity to assignment.

  • 2017

  • Counterfactual Double Lives
    Proceedings of the 21st Amsterdam Colloquium
    // PAPER (pdf)

    We sometimes lead double lives in the consequents of counterfactuals. In counteridenticals like 'If I were you, I would like me.', 'I' and 'me' seem to pick out different individuals. This, I argue, is a problem for the orthodox Kripke-Kaplan view of indexicals as rigid designators, a view which requires 'I' and 'me' to have the same referent in all worlds of evaluation.

    I show this problem is not limited to counteridenticals, but also appears in 'ordinary' counterfactuals like "If I were a policeman, I would arrest me." and modal subordination, as in "I could have been a policeman. I would have arrested me for what I just did." So the problem cannot be solved by a special treatment of counteridenticals. Nor, I argue, can it be analyzed as involving descriptive indexicals. Instead, we should make a more dramatic fix, such as moving to counterpart theory for de re modal ascriptions.



  • Partiality and Objective Value
    at Formal Ethics 2019 (slides) // at the 2019 Pacific APA, Vancouver (handout) // at the 2015 Oxford Grad Conference (handout)
  • Stupefying
    at the 2019 ECOM Workshop, UConn (handout) // at Yale WIP, Spring 2019 (handout)
  • A Plea for Inexact Truthmaking
    at NASSLLI 2018 (poster) // at the 2017 Workshop on Hyperintensional Logics and Semantics, Ghent University (handout)
  • Counterfactual Double Lives
    at the 2017 Amsterdam Colloquium (slides)
  • Counterfactual Donkeys Don't Get High
    at Sinn und Bedeutung 2017 (slides) // at Lucas Champollion's Spring 2017 seminar, NYU (handout)
  • Offsetting
    at Yale WIP, Fall 2016 (handout)