  Brentano distinguished descriptive psychology from genetic psychology. Where genetic psychology seeks the causes of various types of mental phenomena, descriptive psychology defines and classifies the various types of mental phenomena, including perception, judgment, emotion, etc. According to Brentano, every mental phenomenon, or act of consciousness, is directed toward some object, and only mental phenomena are so directed. This thesis of intentional directedness was the hallmark of Brentano’s descriptive psychology. In 1889 Brentano used the term “phenomenology” for descriptive psychology, and the way was paved for Husserl’s new science of phenomenology.