Читать книгу Abnormal Psychology - William J. Ray - Страница 53

Between the time of Galen and the Renaissance, Western science and medicine remained fairly stagnant, with little new knowledge being added. One problem during this period was that authority, which was often the Church, determined what was true or not. Since authority was able to use its own standard of truth, it was difficult to argue another position. For example, the Church was able to say that the earth was the center of the universe, and that was that.

Beginning in the fourteenth century, however, a new spirit began to emerge in Europe. It influenced art, literature, politics, and science. In art, there was a desire for a sense of realism, which led artists such as Leonardo da Vinci to carefully study the human body. He performed dissections on animals and human cadavers to carefully reveal the structure of organs. Figure 1.5 shows one of da Vinci’s drawings.

With the detailed drawings of human anatomy created by da Vinci and other artists of the time, there was now the possibility for the scientists of the 1600s to consider function. One important focus was the manner in which the nervous system allows us to perform both involuntary and voluntary functions. How physiological processes are involved in remembering, moving, feeling, and thinking became topics of consideration. Mechanical models emerged, as illustrated by the writings of French philosopher René Descartes (1596–1650).

Figure 1.5 Leonardo da Vinci Drawing of the Structure of Human Organs

Public domain

Descartes was intrigued by mechanical machines such as the large clocks in Europe with moving figures or water displays in large fountains. By analogy, he assumed that reflexes or involuntary actions of organisms were based on similar principles. Thus, moving your hand quickly from a hot stove or even digesting food was seen as a mechanical operation. For Descartes, all animal behavior could be explained by mechanical principles as could human involuntary actions. In Figure 1.6 from Descartes’ work, you can see the mechanical means by which a hot fire would cause an involuntary or reflexive movement.

The important distinction that continues today is that behavior can be categorized as either involuntary or voluntary. Voluntary actions such as thinking or consciously performing an act were different in that they required a mind, and humans were the only organism to have a mind, according to Descartes. By thinking, humans can know with certainty that they exist—thus, the famous philosophical statement of Descartes, “I think, therefore I am.”

Given the understanding that the bodies of animals are totally mechanical and that humans have both a body and a mind, Descartes created a mind–body distinction that science has had to face in its explanations. The problem is, how can a material body including the brain be influenced by an immaterial process such as the mind? How can a thought influence a cell in the brain?

Figure 1.6 Involuntary or Reflexive Movement

Source: Public domain

Although today we generally talk about the mind–body problem, the metaphysics of Descartes’ era would often make the distinction between body and soul. Descartes answered this problem by suggesting that the rational soul was able to control the mechanical body by having both functions come together in one particular organ of the brain, the pineal gland. It is in the pineal gland, Descartes claimed, that the mind not only controls the body but also senses the nature and flow of the mechanical nervous system.

Today, most neuroscientists see the mind as resulting directly from the brain and that the mind–body problem is not actually a problem to be solved. However, the question of whether particular behaviors seen in individuals with mental illness represent involuntary processes performed without the benefit of a conscious mind has plagued our legal understanding of mental illness.

In the 1600s, science as a way of knowing about the world began to emerge. At the beginning of this period, prior authorities such as Aristotle or the Church determined the worldview. In this century, Galileo led a movement that would eventually replace authority with experimentation. This movement toward experimentation was greatly aided by Galileo’s own inventions, such as the telescope, the thermometer, an improved microscope, and a pendulum-type timing device. Each of these instruments allowed people to experiment and answer for themselves the questions of nature. With Galileo’s work, a new science based on observation and experimentation was beginning. Galileo was part of a revolution that was to challenge authority. In the 1680s, Newton’s classic work Principia was published (Newton, 1729/1969). Designated by science historian Gerald Holton (1952) as “probably the greatest single book in the history of science,” this work describes Newton’s theories of time, space, and motion as well as his rules of reasoning for science.

Concept Check

 Concepts in understanding psychopathology date back thousands of years yet still influence our views today. What important contributions did the ancient Greeks and Romans—particularly Pythagoras, Hippocrates, and Galen—make to current views of psychopathology?

 Describe the shift from authority to science as a way of knowing what happened during the Renaissance. Specifically, what did Leonardo da Vinci, René Descartes, Galileo, and Isaac Newton contribute during this period that led to this shift?