difference. Nothing must be taken for granted, and nothing must be
assumed. Psychology, then, is like all the other sciences, in that its
method of getting its facts is by observation and experiment.

SUMMARY. Science is systematic, related knowledge. Each science has
a particular field which it attempts to explore and describe. The
field of psychology is the study of sensitivity, action, and
consciousness, or briefly, human behavior. Its main problems are
development, heredity, instincts, habits, sensation, memory,
thinking, and individual differences. Its method is observation and
experiment, the same as in all other sciences.


CLASS EXERCISES

1. Make out a list of things about human nature which you would like to
know. Paste your list in the front of this book, and as you find your
questions answered in this book, or in other books which you may read,
check them off. At the end of the course, note how many remain
unanswered. Find out whether those not answered can be answered at the
present time.

2. Does everything you do have a cause? What kind of cause?

3. Human nature is shown in human action. Human action consists in
muscular contraction. What makes a muscle contract?

4. Plan an experiment the object of which shall be to learn something
about yourself.