Date of Award

Spring 1-1-2016

Document Type


Degree Name

Doctor of Philosophy (PhD)



First Advisor

Robert D. Rupert

Second Advisor

Carol Cleland

Third Advisor

Graham J. Oddie

Fourth Advisor

Iskra N. Fileva

Fifth Advisor

Clayton H. Lewis


Some authors in philosophy of mind have sought to defend a theory according to which cognitive processing and/or mental states substantively extend beyond the bounds of an individual’s body. The Extended Mind Thesis (EMT) asserts that the vehicles of cognition and mental states exist at least partly outside of the human thinker. This dissertation introduces and defends one new objection to EMT. My focus here will be on what I call the agency problem for the extended mind, which asserts that EMT cannot account for intentional action or human agency. I shall argue that EMT cannot explain genuine intentional actions, the ability to perform which is a central part of our identity as human persons. If we believe EMT, then we give up our last grasp of causal sovereignty when it comes to our actions. I use these arguments to motivate a conservative view of the mind as an embodied, but not substantively extended, entity.