Can We have Justified Beliefs about Fundamental Properties?

An attractive picture of the world is that some features are metaphysically fundamental and others are derivative, with the derivative features grounded in the fundamental features. But how do we have justified beliefs about which features are fundamental? What is the epistemology of fundamentality? I sketch a response in this paper. The guiding idea is that the same properties cause the same experiences. I argue that a probabilistic connection between epistemic fundamentality and metaphysical fundamentality is sufficient for justified beliefs about the metaphysically fundamental.