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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 to critical thinking. Psychologists encourage what William James called (in the 1890s) "the habit of seeing the alternative." Researchers in psychology emphasize evidence in evaluating claims. We discuss the concept of evidence and how understanding it requires some literacy in science.

The following sections cover some 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.

Two sections cover 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!")

So this integrating theme will remain largely implicit (unspoken) except in the chapter introductions, like this one, or where creative synthesis is key to understanding the subject matter, as when discussing errors of memory.

How does the creative brain relate to this 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 elaborated on the page titled The Role of Science. There I argue that the whole purpose of science is to model the natural universe, much as the brain models the inner and outer world for us.

The same theme surfaces on a page titled The Two Powers of Science. There I suggest the two major categories of research, observational and experimental, mimic and amplify two abilities of the human brain: 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 generally presented in the context of a topic. For example, the history of memory research is discussed in Chapter 6 (Memory). Principles of scientific thought also appear in many other chapters, often with backward references to concepts in this chapter.

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