CHAPTER 1—PERSONALITY AND THE SCIENTIFIC OUTLOOK
CHAPTER OUTLINE
I. Why study personality? The study of human personality helps us understand ourselves and
other people better and gives us a greater appreciation for the complexity of human
experience.
II. Definition of Personality: Personality is the dynamic and organized set of characteristics
possessed by an individual that uniquely influences his or her cognitions, motivations and
behaviors in various situations.
III. Personality and Science: Personality is a scientific enterprise concerned with the description,
explanation, prediction, and control of events.
A. Components of Science: Theories and Research Methods
1. What are theories? A theory is a system of interrelated conceptual statements that are
created by investigators to account for a phenomenon or a set of phenomena.
2. Kinds of theories
a. inductive-sets of general summary statements about phenomena derived from facts.
b. deductive-theories in which specific hypotheses are derived from abstract propositions
and then tested by the collection of data. Deductive theories consist of postulates,
propositions, conceptual definitions, operational definitions, hypotheses, and empirical
observations.
1. postulates-the fundamental or core assumptions of a theory. They are taken as self-
evidently true in order to provide a clear and focused direction for theorizing and
research.
2. propositions- general relational statements that may be true or false. They are not tested
directly; instead, hypotheses are derived from them.
3. hypotheses-specific propositions containing constructs that are conceptually defined and
operationalized so they can tested and confirmed or disconfirmed through empirical
testing. Hypotheses are tentative theoretical statements about how events are related to
one another, often stated as predictions.
a. a prior predictions-predictions made before the collection of data.
4. conceptual definitions- concepts in the hypotheses are defined precisely so that accurate
measures of the concepts can be devised.
5. operational definitions- procedures (or operations) used to define particular constructs.
6. empirical observations-observations of phenomena made by investigators.
1
,1V. Research Methods Used to Test Theories
A. Experimental Method-technique for studying cause-and- effect relationships between
variables. It involves the manipulation of independent variables and observation of the
effects of the manipulation(s) on dependent variables.
1. independent variables-the variables actively manipulated by the experimenter so that
their effects on individual behavior can be observed.
2. dependent variables-changes in behavior that occur as a result of the manipulation of
conditions by an experimenter.
3. control group-the group that does not receive the experimental treatment. It is designed
to provide baseline data against which the effects of the experimental manipulation(s) on
the dependent variable(s) can be accurately judged.
B. Correlational Method-general procedure for establishing an association or relationship
between events.
1. positive correlation-increases in the scores on one variable are associated with increases
in the scores on the other variable.
2. negative correlation-increases in the scores on one variable are associated with
decreases in the scores on the other.
3. no relation-the distributions of scores on the two variables are random
C. Case Study Method-technique involving the intensive study of a single person in order to
understand his or her unique personality and behavior.
1. post-hoc explanation-explanation of a phenomenon given after its occurrence.
V. Ethics for Conducting Research
A. informed consent-the practice of telling study participants about the nature of their
participation in a proposed experiment and then obtaining their written agreement to
participate.
B. debriefing-informing study participants of the true nature and purpose of a study after it is
completed.
VI. Criteria for Evaluating Theories
A. Comprehensiveness-theories are judged as more adequate and useful if they encompass
and account for a wide range and variety of phenomena.
B. Precision and testability- adequate theories should contain constructs and relational
statements that are clearly and explicitly stated and measured. Under such conditions,
theories can be more accurately tested.
C. Parsimony- adequate theories should be as economical as possible, while still adequately
accounting for the phenomena in their domain.
D. Empirical validity- the hypotheses of theories are tested by the collection of data to
determine whether or not they are accurate.
2
,E. Heuristic value- adequate theories should be challenging; they should stimulate new ideas
and new research.
F. Applied value- adequate theories are capable of providing creative solutions to problems
that are of interest and concern to people in society.
3
, CLASSROOM TOPICS FOR LECTURE, DISCUSSION, AND DEMONSTRATION
Judging the Scientific Worth of a Theory: Which Criterion is Most Important? Present the 6
criteria for judging the scientific worth of a theory and ask the students which one of them is the
most important. Since most students, especially those who have taken several courses in
psychology, are imbued with the need to have data to support whatever conclusions they reach
and will immediately say empirical validity. You can then mention that you're not so sure. You
can create a theory on the spot that lacks comprehensiveness but has massive empirical
support. Walk up the classroom aisle until you find a male and a female sitting next to one
another. Then tell the students you will create a theory of infatuation, saying that if the female
likes the male sitting next to her, she will figure that if she sits next to him at each session, that
they will begin to talk, come to like one another, and that he will eventually ask her out. Then
tell the class that you predict on the basis of your theory that, class after class, she will sit next
to him. And she does; thus, there is massive empirical support for your theory. Point out that
while the theory has massive empirical support, it's not the most useful theory in the universe.
It's too limited. It can't compare with the comprehensiveness of Freud's theory which explains
vast numbers of phenomena, e.g., marriage, war, friendship, incest, dreams, accidents on the
job, even though empirical support for the theory is mixed. As another example, you can
mention that, if a theory is imprecise and therefore the scientist is unable to test it adequately,
it will very likely yield data that are questionable. So the theory's empirical validity depends on
its precision and testability. You can then draw the conclusion that all of the criteria are
important and interrelated and that it makes little sense to argue that any one criterion by itself
is most important.
LEARNING GOALS
At the conclusion of Chapter 1, your students should be able to:
1. define personality from the perspective of professional personality psychologists and
from the perspective of laypeople and to explain why personality psychologists see
laypeople's definition of the term as inadequate and unscientific.
2. define scientific theory and to describe the differences between deductive and inductive
theories.
3. define research methods and to explain the differences between the experimental,
correlational, and case study techniques.
4. describe the differences between a priori and post hoc explanations.
5. name the six criteria that are used by personality psychologists to judge the scientific
worth of theories and to be able to give a rationale for why the criteria are all
4
CHAPTER OUTLINE
I. Why study personality? The study of human personality helps us understand ourselves and
other people better and gives us a greater appreciation for the complexity of human
experience.
II. Definition of Personality: Personality is the dynamic and organized set of characteristics
possessed by an individual that uniquely influences his or her cognitions, motivations and
behaviors in various situations.
III. Personality and Science: Personality is a scientific enterprise concerned with the description,
explanation, prediction, and control of events.
A. Components of Science: Theories and Research Methods
1. What are theories? A theory is a system of interrelated conceptual statements that are
created by investigators to account for a phenomenon or a set of phenomena.
2. Kinds of theories
a. inductive-sets of general summary statements about phenomena derived from facts.
b. deductive-theories in which specific hypotheses are derived from abstract propositions
and then tested by the collection of data. Deductive theories consist of postulates,
propositions, conceptual definitions, operational definitions, hypotheses, and empirical
observations.
1. postulates-the fundamental or core assumptions of a theory. They are taken as self-
evidently true in order to provide a clear and focused direction for theorizing and
research.
2. propositions- general relational statements that may be true or false. They are not tested
directly; instead, hypotheses are derived from them.
3. hypotheses-specific propositions containing constructs that are conceptually defined and
operationalized so they can tested and confirmed or disconfirmed through empirical
testing. Hypotheses are tentative theoretical statements about how events are related to
one another, often stated as predictions.
a. a prior predictions-predictions made before the collection of data.
4. conceptual definitions- concepts in the hypotheses are defined precisely so that accurate
measures of the concepts can be devised.
5. operational definitions- procedures (or operations) used to define particular constructs.
6. empirical observations-observations of phenomena made by investigators.
1
,1V. Research Methods Used to Test Theories
A. Experimental Method-technique for studying cause-and- effect relationships between
variables. It involves the manipulation of independent variables and observation of the
effects of the manipulation(s) on dependent variables.
1. independent variables-the variables actively manipulated by the experimenter so that
their effects on individual behavior can be observed.
2. dependent variables-changes in behavior that occur as a result of the manipulation of
conditions by an experimenter.
3. control group-the group that does not receive the experimental treatment. It is designed
to provide baseline data against which the effects of the experimental manipulation(s) on
the dependent variable(s) can be accurately judged.
B. Correlational Method-general procedure for establishing an association or relationship
between events.
1. positive correlation-increases in the scores on one variable are associated with increases
in the scores on the other variable.
2. negative correlation-increases in the scores on one variable are associated with
decreases in the scores on the other.
3. no relation-the distributions of scores on the two variables are random
C. Case Study Method-technique involving the intensive study of a single person in order to
understand his or her unique personality and behavior.
1. post-hoc explanation-explanation of a phenomenon given after its occurrence.
V. Ethics for Conducting Research
A. informed consent-the practice of telling study participants about the nature of their
participation in a proposed experiment and then obtaining their written agreement to
participate.
B. debriefing-informing study participants of the true nature and purpose of a study after it is
completed.
VI. Criteria for Evaluating Theories
A. Comprehensiveness-theories are judged as more adequate and useful if they encompass
and account for a wide range and variety of phenomena.
B. Precision and testability- adequate theories should contain constructs and relational
statements that are clearly and explicitly stated and measured. Under such conditions,
theories can be more accurately tested.
C. Parsimony- adequate theories should be as economical as possible, while still adequately
accounting for the phenomena in their domain.
D. Empirical validity- the hypotheses of theories are tested by the collection of data to
determine whether or not they are accurate.
2
,E. Heuristic value- adequate theories should be challenging; they should stimulate new ideas
and new research.
F. Applied value- adequate theories are capable of providing creative solutions to problems
that are of interest and concern to people in society.
3
, CLASSROOM TOPICS FOR LECTURE, DISCUSSION, AND DEMONSTRATION
Judging the Scientific Worth of a Theory: Which Criterion is Most Important? Present the 6
criteria for judging the scientific worth of a theory and ask the students which one of them is the
most important. Since most students, especially those who have taken several courses in
psychology, are imbued with the need to have data to support whatever conclusions they reach
and will immediately say empirical validity. You can then mention that you're not so sure. You
can create a theory on the spot that lacks comprehensiveness but has massive empirical
support. Walk up the classroom aisle until you find a male and a female sitting next to one
another. Then tell the students you will create a theory of infatuation, saying that if the female
likes the male sitting next to her, she will figure that if she sits next to him at each session, that
they will begin to talk, come to like one another, and that he will eventually ask her out. Then
tell the class that you predict on the basis of your theory that, class after class, she will sit next
to him. And she does; thus, there is massive empirical support for your theory. Point out that
while the theory has massive empirical support, it's not the most useful theory in the universe.
It's too limited. It can't compare with the comprehensiveness of Freud's theory which explains
vast numbers of phenomena, e.g., marriage, war, friendship, incest, dreams, accidents on the
job, even though empirical support for the theory is mixed. As another example, you can
mention that, if a theory is imprecise and therefore the scientist is unable to test it adequately,
it will very likely yield data that are questionable. So the theory's empirical validity depends on
its precision and testability. You can then draw the conclusion that all of the criteria are
important and interrelated and that it makes little sense to argue that any one criterion by itself
is most important.
LEARNING GOALS
At the conclusion of Chapter 1, your students should be able to:
1. define personality from the perspective of professional personality psychologists and
from the perspective of laypeople and to explain why personality psychologists see
laypeople's definition of the term as inadequate and unscientific.
2. define scientific theory and to describe the differences between deductive and inductive
theories.
3. define research methods and to explain the differences between the experimental,
correlational, and case study techniques.
4. describe the differences between a priori and post hoc explanations.
5. name the six criteria that are used by personality psychologists to judge the scientific
worth of theories and to be able to give a rationale for why the criteria are all
4
