Story of Psychology - Morton Hunt [158]
How could it enlighten human beings about their own minds to harness a dog in a box, start a metronome ticking for fifteen seconds, then drop some meat powder in a bowl inside the box, and repeat this process until at the sound of the metronome saliva would drip from the dog’s mouth even though the meat powder had not yet been delivered? Many psychologists, when they first heard about this experiment, said that it represented a type of association that accounted for only simple forms of behavior in animals; the researcher, however, believed that the principle he had discovered would explain even the most advanced and complex forms of behavior in human beings.3
These experiments and many like them were part of a bold attempt, beginning at the end of the nineteenth century, to answer—actually, to eliminate from discussion—the most perplexing and intractable problems of psychology: those having to do with the nature of mind. Among them:
—What is it within us that sees, feels, and thinks, every moment we are awake, vanishes temporarily when we sleep (or, if we dream, seems to leave the body and travel elsewhere), and disappears permanently the instant we die? Is it identical with, or a part of, the soul? Or is it something else equally nonmaterial?
—In either case, how could a nonmaterial essence—not even a vapor, not even a shadow—exert any influence on the material body it inhabits, and how could it feel the body’s sensations?
—Does it endure after the body dies—and if so, where? And lacking any connection with sense organs and nerves after death, how can it perceive anything of whatever realm it inhabits?
These were but a few of the questions about the nature of mind, mental states, and the processes of thinking that philosophers, theologians, and protopsychologists had long sought to answer, though their efforts created more puzzles than they solved.
There was, however, another and totally different answer to such questions, though it was abhorrent to most philosophers and psychologists. Mind is an illusion; there is no incorporeal self within us; our mental experiences, including consciousness, awareness of self, and thinking, are only physiological events taking place in the nervous system in response to stimuli.
Over the centuries a few materialist philosophers suggested this alternative in vague and unconvincing terms, but as the physical and physiological sciences developed, the hypothesis became increasingly specific and plausible. By the latter half of the nineteenth century, Helmholtz and a number of other physiologists were linking simple sensations to electrochemical events in the sensory nerves, and followers of Wundt were beginning their effort to construct a whole psychology out of the elemental components of sensation and perception.
Toward the end of the century the rejection of “mentalism” (the belief in mind as a separate essence) gained support from a quite different quarter—animal psychology, a field in which interest had been sparked by Darwin’s demonstration of the link between humankind and the other species. At first some biologists and psychologists had assumed that animals possess thought processes similar to, though simpler than, our own; in the 1880s, George Romanes, an English biologist, explored animal psychology through “introspection by analogy”; he asked himself what he would do were he the animal in any given situation. But in 1894 the zoologist C. Lloyd Morgan—the researcher who offered two kinds of caterpillars