Elements of Psychophysics, Vol. I

II. Concept and Task of Psychophysics.

By psychophysics, we should here understand an exact theory of the functional or dependency relationships between the body and the soul, or more generally, between the physical and the psychological, the material and the mental worlds.

To the realm of the mental, the psychological, or the soul, we generally assign everything that can be grasped through inner perception Inner perception: The ability to observe one's own conscious thoughts, feelings, and sensations (often called introspection). or can be abstracted from it. To the realm of the physical, the corporeal, or the material, we assign that which is graspable through outer perception or can be abstracted from it. These terms are intended merely to designate the spheres of the "world of appearance" original: "Erscheinungswelt". Fechner uses this term in a Kantian sense, referring to the world as we experience it through our senses, rather than the "ultimate reality" that might exist behind it. with whose relationship psychophysics will concern itself. It is assumed that one understands "inner" and "outer" perception in the sense of common usage, referring to those activities through which existence in general becomes manifest as an appearance.

All discussions and investigations in psychophysics relate solely to the side of appearance of the physical and mental worlds—to that which appears directly through inner or outer perception, or is inferable from what appears, or is graspable as a relationship, category, connection, sequence, or law of what appears. In short, it deals with the physical in the sense of physics and chemistry, and with the psychological in the sense of empirical psychology original: "Erfahrungsseelenlehre". Literally "experience-soul-teaching," referring to psychology based on observation rather than philosophical deduction., without regressing in any way to the "essence" of the body or the soul behind the world of appearance in the sense of metaphysics Metaphysics: The branch of philosophy that deals with abstract concepts like "being" and "essence" that cannot be directly measured or observed..

Generally, we call the mental a function of the physical, or dependent upon it, and vice-versa, insofar as such a constant or lawful relationship exists between the two that the existence and changes of one can be inferred from those of the other.

Handwritten mark (similar to 'd') The fact of functional relationships between body and soul is generally undisputed; however, an undecided conflict remains regarding the reasons, the interpretation, and the extent of this fact.

Without regard for the metaphysical viewpoints of this conflict—which relate more to the so-called "essence" than to the appearance—psychophysics attempts to [capture] the act-