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Chapter One: Psychology and Science

Table of Contents

Part One: What is Psychology?

Part Two: The History of Psychology

Part Three: Critical Thinking

Part Four: Observational and Experimental Research

Overview of Chapter 1: Psychology and Science

The purpose of this chapter is to introduce the field of psychology. We will also discuss some basic principles of critical thinking and two basic forms of scientific research used by psychol­ogists: observational and experimental research.

How this chapter is organized

We start with a definition of the field and a brief discussion of the different types of psychologists. Next we review some of the history of psychology.

Psychology has been through many changes in emphasis during its years of existence. In some ways it has come in a full circle. The initial concern was mind and consciousness in the mid-1800s.

Then the field switched to emphasize observable behavior in the mid-20th Century, during the era when behaviorism dominated. In the second half of the 20th Century onward, there was a revival of interest in mind and consciousness, aided by new tools such as computers an brain scanning.

We will discuss four ways of analyzing psychological data that today co-exist in relative harmony: the biological, the behavioral, the cognitive, and the subjective or phenom­enological approaches.

Following the history of psychology, we turn in Part Three to critical thinking. Psychologists encourage what William James called (in the 1890s) "the habit of seeing the alternative." We discuss the concept of evidence and how understanding it requires some literacy in science.

The remainder of the chapter covers the basics of scientific research. We start with the process of making operational definitions, always necessary when gathering evidence. Then we examine fake or quack science and how it differs from real science.

Part Four is about two different kinds of research used in psychology: observational and experimental research. We examine the potential pitfalls of both, relating this back to the idea of critical thinking.

The Creative Brain

Throughout this book a theme that surfaces in almost every chapter is the creativity of the human brain. Virtually all the evidence from various branches of psychology points to the conclusion that all our psychological processes, including all the subtleties of our thoughts, emotions, consciousness and social relations, are produced by the brain.

This implies that the brain has tremendous creative powers. The brain is a superb audio/visual synthesizer. It is also a learner, planner, communicator, feeler, and thinker, and much more. The brain constructs our entire complex human experience. The implications of this are vast.

However, this principle is so relevant to so much of psychology that you might get tired of having it constantly pointed out. ("Look! Look! Another example of the creative brain!")

Therefore this integrating theme will remain largely under the surface except in chapter intro­ductions, like this one, where it will be pointed out. It will also come up when creative synthesis is key to a subject matter such as perception or memory.

How does the creative brain relate to this first chapter, with its emphasis on scientific method? Science itself is a product of creative brains, of course, but there is a deeper similarity between science and the brain.

Science is like an extension of the brain's reality-modeling capabilities. That idea is discussed on the page titled The Role of Science. The whole purpose of science is to model natural systems, much as the brain models the inner and outer world for us.

A similar theme of scientific research mimicking human intelligence appears on the page titled The Two Powers of Science. Observational and experimental research, respectively, are very much like two different human intellectual abilities: intuition and analysis.

Related Topics in Other Chapters

Specialties of psychology are discussed in greater depth throughout the book. Historical material, except for the quick survey in this chapter, is presented in context. Principles of scientific thought also appear in many other chapters, often with backward references to concepts in this chapter.

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