Turtles all the way down: regress, priority and fundamentality in metaphysics

This paper is a discussion of an intuition commonly held by metaphysicians: that there must be a fundamental layer of reality; that chains of ontological dependence must terminate; that there cannot be turtles all the way down. I discuss application of this intuition with reference to Bradley’s regress, composition, realism about the mental and the cosmological argument. I discuss some arguments for the intuition, but argue that they are unconvincing. I conclude by making some suggestions for how the intuition should be argued for, and discussing the ramifications of giving the justification I think best.