Ari Deller

Ari Deller

PhD Candidate in Philosophy · University of Cambridge

I work in epistemology, ethics, and the philosophy of artificial intelligence.

I am a PhD candidate in Philosophy at the University of Cambridge, where I am a Peterhouse Graduate Scholar supervised by Jessie Munton and Richard Holton. In Spring 2025 I was a Visiting PhD Researcher at MIT. Before Cambridge I read for the BPhil at Oxford and an MA at Edinburgh.

My research concerns epistemic agency and how it comes under two practical pressures:

  1. the demands of ethics;
  2. the proliferation of increasingly capable artificial intelligence.

My doctoral thesis, Epistemic Agency and Practical Pressures, pursues this theme across the grounds of epistemic normativity, the morality of belief, and the epistemic stakes of living alongside persuasive AI.

Alongside my doctoral work, I hold fellowships in AI governance and safety — currently as an ERA:AI Governance Fellow and a Fellow of the Cambridge AI Safety Hub.

Research interests

Recent work

The Epistemic Costs of Super-Persuasive AI

Philosophy & Technology 39:2 (2026), art. 92.

Argues that AI which is highly persuasive but not reliably truthful imposes real epistemic costs — chief among them, a pervasive undercutting defeat of beliefs we form through argument. Read more →