If one takes a broad perspective on the development of Western psychotherapy, looking in the broadest possible terms at everything that has been written under the umbrella of “psychology”, the most natural way of dividing the field is between those thinkers who predominantly sought to use subjective observations about the nature and behavior of their own mind to establish an understanding of how all human minds work, versus those who sought to use the outward manifestations of human consciousness, typically research generated by scientific studies and brain imaging, to better grasp what lies within. Owing to the former's reliance on the experience of a single mind and the latter's foundation in experimental research, we can call these two camps experiential and experimental psychology.