Existential-humanistic (E-H) psychology is the study of human existence.
Psychology in general is the science of mental processes (mind) and behavior.
Thus, E-H psychology enlarged is the science of mind and behavior within human existence.
But what is human existence with no mind? Mind is a necessary feature; for without it, we’d have no room to consider human existence to begin with.
Behavior may be said to pervade all levels of reality. In physics, we speak of the behavior of particles. Social science considers the situational behavior of persons as human beings.
Mind and behavior are thus part-and-parcel of human existence. Our science of the former two topics must serve to bolster our understanding–and, ultimately, experience–of the latter.
As minded human persons who behave situationally, how do we experience our existence?