Husserl’s transcendental phenomenology is first and foremost a science of the structures of consciousness. Since it is intended to yield eidetic, i. e., a priori insights, it is often assumed that transcendental phenomenology and the natural sciences are totally detached from each other such that phenomenological investigations cannot possibly benefit from empirical evidence. The aim of this paper is to show that a beneficial relationship is possible. To be more precise, I will show how Husserl’s a priori investigations on consciousness (...) can be supplemented by research in experimental psychology in order to tackle fundamental questions in epistemology. Our result will be a phenomenological conception of experiential justification that is in accordance with and supported by empirical phenomena such as perceptual learning and the phenomenon of blindsight. Finally, I shall shed light on the systematic limits of empirical research. (shrink)