1Although the content and character of economics cannot be described briefly, numerous writers have attempted that.2 An especially useless, though once popular, example is: «Economics is what economists do.»3 notable economist of the last century Alfred Marshall called economics «a study of mankind in the ordinary business of life.»4We may make better progress by comparing economics
 with other subjects. Like every other discipline that attempts to 
explain observed facts (e.g., physics, astronomy, meteorology), 
economics comprises a vast collection of descriptive material organized 
around a central core of theoretical principles. The manner in which 
theoretical principles are formulated and used in  applications 
varies greatly from one science to another. Like psychology, economics 
draws much of its theoretical core from intuition, casual observation, 
and «common knowledge about human nature.» Like astronomy, economics is 
largely nonexperimental. Like meteorology, economics is relatively 
inexact, as is weather forecasting. Like particle physics and molecular 
biology, economics deals with an array of closely interrelated phenomena
 (as do sociology and social psychology). Like such disciplines as art, 
fantasy writing, mathematics, metaphysics, cosmology, and the like, 
economics attracts different people for different reasons: «One person’s
 meat is another person’s poison.» Though all disciplines differ, all 
are remarkably similar in one respect: all are meant to convey an 
interesting, persuasive, and intellectually satisfying story about 
selected aspects of experience. As Einstein once put it: «Science is the
 attempt to make the chaotic diversity of our sense-experience 
correspond to a logically uniform system of thought.»