Dr Juhani Yli-Vakkuri

Senior Research Fellow

Professor Juhani Yli-Vakkuri

Areas of expertise: philosophy of language; philosophy of mind; metaphysics; epistemology

ORCID ID: 0000-0001-6929-0913

Location: ACU Melbourne Campus

Juhani Yli-Vakkuri works in metaphysics and epistemology, broadly construed. Much of his work has been concerned with semantic compositionality, vagueness, the interaction of epistemic with objective modalities, the nature of mental content, and the metaphysics and epistemology of modality. 

Most recently, Dr Yli-Vakkuri’s work has focused on semantic internalism vs. externalism, modal metaphysics, and the idea of vagueness as a special kind of obstacle to knowledge. In Narrow Content (Oxford University Press, 2018), he and John Hawthorne opened up a new line of attack against varieties of semantic internalism, focusing on the theoretical roles internalists had carved out for narrow mental content (mental content determined entirely by the internal state of the subject). In Living on the Edge: Puzzles of Modal Variation (in preparation, co-authored with Cian Dorr and John Hawthorne) he examines a cluster of puzzles in modal metaphysics in the vicinity of Chisholm’s paradox, and defends a novel solution to them that relies on a combination of a plenitudinous ontology (according to which any physical object is coincident with a vast number of other physical objects) and semantic plasticity (according to which nearly all of our words could very easily have had different meanings). In Vagueness and Ignorance (in preparation, co-authored with John Hawthorne) he argues that there is no such thing as vagueness, in the philosophers’ various technical senses of ‘vagueness’, and that the only interesting feature our paradigms of vagueness have in common is that they concern facts that are, for a variety of reasons, ‘too difficult to know’.

Dr Yli-Vakkuri received his bachelor’s degree from UCLA, and his doctorate from the University of Oxford in 2012. He has worked at the University of Oslo, Bielefeld University, and the University of Tartu, where he also holds the position of Professor of Philosophy of Language.

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Select publications


  • Narrow Content (with John Hawthorne). Oxford: Oxford University Press, 2018.
  • Williamson on Modality (edited, with Mark McCullagh). London: Routledge, 2017.


  • “The Necessity of Mathematics”, Noûs, published online-first, 17 September 2018 (with John Hawthorne).
  • “Operator Arguments Revisited”, Philosophical Studies, Vol. 176, (2019), pp. 2933–2959 (with John Hawthorne and Peter Fritz).
  • “Knowledge of Objective Modality”, Philosophical Studies, Vol. 176 (2019), pp. 1155–1175 (with Margot Strohminger).
  • “Semantic Externalism without Thought Experiments”, Analysis, Vol. 78 (2018), pp. 81–89.
  • “The Epistemology of Modality”, Analysis, Vol. 77 (2017), pp. 825-838 (with Margot Strohminger).
  • “Vagueness and Modality”, Philosophical Perspectives, Vol. 30 (2016), pp. 229–269 (with Jon Litland).
  • “Epistemicism and Modality”, Canadian Journal of Philosophy, Vol. 46, Nos. 4-5 (2016), pp. 803–835.
  • “Propositions and Compositionality”, Philosophical Perspectives, Vol. 27 (2013), pp. 526-563.

Appointments and affiliations

  • Professor of Philosophy of Language, University of Tartu, 2018-present
  • Associate Faculty Member, Faculty of Philosophy, University of Oxford, 2018-present
  • Alexander von Humboldt Research Fellow, Bielefeld University, 2016-2018
  • Postdoctoral Research Fellow, Centre for the Study of Mind in Nature, University of Oslo, 2012-2015

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