I am a Junior Research Fellow in Philosophy at Merton College, Oxford University. My research focuses on contemporary theories of liberalism. In particular, I am interested in various principles of liberal political morality, such as the harm principle, the principle of state neutrality, and the public justification principle.

Prior to this, I read a DPhil in Philosophy at St John's College, Oxford University (2017-19), a BPhil in Philosophy at The Queen's College, Oxford University (2015-17), and an undergraduate degree in Philosophy, Politics and Economics at Lincoln College, Oxford University (2012-15). 

Email: collis.tahzib@philosophy.ox.ac.uk


1.."Pluralist Neutrality", Journal of Political Philosophy 26 (2018), pp. 508-32.

2.."Perfectionism: Political not Metaphysical", Philosophy & Public Affairs 47 (2019), pp. 144-78.

3.."Does Social Trust Justify the Public Justification Principle?" Journal of Applied Philosophy (forthcoming).

4.."Perfectionist Duties", in D. Sobel, P. Vallentyne and S. Wall (eds), Oxford Studies in Political Philosophy Volume 7 (Oxford: Oxford University Press, forthcoming). 

5.."Does Edificatory Perfectionism Express a Quidnunc Mentality?", in V. Kurki and M. McBride (eds), Without Trimmings: The Legal, Moral, and Political Philosophy of Matthew Kramer (Oxford: Oxford University Press, forthcoming). 

6.."Do the Reactive Attitudes Justify Public Reason?" European Journal of Political Theory (forthcoming).

Recent talks

1.   "Perfectionist Principles of Justice" at University of Rijeka, February 2020.

2.   "Deontic Perfectionism" at University of Southern California, January 2020.

3. "Deontic Perfectionism" at 7th Annual Workshop for Oxford Studies in Political Philosophy, Syracuse, NY, August 2019.

4. "Does Edificatory Perfectionism Express a Quidnunc Mentality?" at Conference in Honour of Matthew Kramer, Cambridge, July 2019.