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C H A P T E R 1
Economics : What is
Economics?
Objectives
After studying this chapter, you will be able to:
Define economics and distinguish between
microeconomics and macroeconomics
Explain the two big questions of economics
Explain the key ideas that define the economic way
of thinking
Explain how economists go about their work as
social scientists
Definition of Economics
All economic questions arise because we want
more than we can get.
Our inability to satisfy all our wants is called
scarcity.
Because we face scarcity, we must make choices.
The choices we make depend on the incentives
we face.
An incentive is a reward that encourages an
action or a penalty that discourages an action.
Definition of Economics
Economics is the social science that studies the
choices that individuals, businesses, governments, and
entire societies make as they cope with scarcity and
the incentives that influence and reconcile those
choices.
Economics divides in to main parts:
 Microeconomics
 Macroeconomics
Two Big Economic Questions
Two big questions summarize the scope of
economics:
How do choices end up determining what, how,
and for whom goods and services get produced?
When do choices made in the pursuit of self-
interest also promote the social interest?
Two big economic questions: What, How and For whom
What?
What we produce changes over time
What determines the quantities and all the other
millions of items that we produce?
How?
Goods and services are produced by using
productive resources that economists call factors of
production.
How? continues..
Factors of production are grouped into four
categories:
- Land
- Labour
- Capital
-Entrepreneurship
How continues..
 The gifts of nature that we use to produce goods and
services are land.
 The work time and work effort that people devote to
producing goods and services is labour.
 The quality of labour depends on human capital, which is
the knowledge and skill that people obtain from
education, on-the-job training, and work experience.
 The tools, instruments, machines, buildings, and other
constructions that businesses use to produce goods and
services are capital.
 The human resource that organises land, labour, and
capital is entrepreneurship.
Two Big Economic Questions: For Whom?
Who gets the goods and services depends on the
incomes that people earn.
 Land earns rent.
 Labour earns wages.
 Capital earns interest.
 Entrepreneurship earns profit.
Two Big Economic Questions: When is the Pursuit of Self-
Interest in the Social Interest?
Every day, 49 million South Africans and 6.6 billion
people in the rest of the world, make economic choices
that result in What, How, and For Whom goods and
services are produced.
Do we produce the right things in the right
quantities?
Do we use our factors of production in the best way?
Do the goods and services go to those who benefit
most from them?
Two Big Economic Questions: When is the Pursuit of Self-Interest in the
Social Interest? Continues..
 You make choices that are in your self-interest
choices that you think are best for you.
 Choices that are best for society as a whole are said
to be in the social interest.
 An outcome is in the social interest if it uses
resources efficiently and distributes goods and
services fairly.
 Is it possible that when each one of us makes choices
that are in our self-interest, it also turns out that
these choices are also in the social interest?
Two Big Economic Questions: When is the Pursuit of Self-Interest in the
Social Interest? Continues..
Five topics that generate discussion and that
illustrate tension between self-interest and social
interest are
 Privatisation
 Globalisation
 HIV/Aids
 Water storages
 Unemployment
The Economic Way of Thinking: Choices and
Trade-offs
 Because of scarcity we must make choices, we select
from the available alternatives.
 You can think about every choice as a tradeoffan
exchangegiving up one thing to get something else.
 The classic tradeoff is guns versus butter.
 Guns and butter stand for any pair of goods.
The Economic Way of Thinking: What, How and
For Whom Trade-offs
What Trade-offs
What goods and services get produced depends on
choices made by each one of us, when governments
choose how to spend their tax revenues, and when
businesses choose what to produce.
How Trade-offs
How goods and services get produced depends on
choices made by the businesses that produce them.
The Economic Way of Thinking: What, How and
For Whom Trade-offs Continues..
For Whom Trade-offs
 For whom goods and services are produced depends
on the distribution of buying power.
 Government redistribution of income from the rich
to the poor creates the big tradeoff - the tradeoff
between equality and efficiency.
The Economic Way of Thinking: Choices Bring
Change
 The quantity and range of goods and services
available today in the US are much greater than
those in Africa.
 The Economic condition of the world today is much
better than it was a generation ago.
 The quality of economic life depends on many of the
choices made by each one of us and these choices
involve trade-off.
The Economic Way of Thinking: Choices Bring
Change Continues..
One choice is that of how much of our income to
consume and how much to save. If we save more, we can
buy more capital and increase our production.
A second choice is how much effort to devote to
education and training. If we take less leisure time, we can
educate and train ourselves to become more productive.
A third choice is how much effort to devote to research
and development of new products and production
methods. If businesses produce less and devote resources
to research and developing new technologies, they can
produce more in the future
The Economic Way of Thinking: Opportunity
Cost
 The opportunity cost of something is the highest-
valued alternative that we give up to get it. In other
words it is the value of the NEXT BEST opportunity
that is sacrificed by the exercise of a choice
 For instance if you have three items in front of you,
namely: a chocolate, a toffee and jelly babies.
 Arrange these items according to you preference
(what you like most to what you like least).
 Example chocolate, jelly babies and toffee. Chocolate
is your first choice hence you will sacrifice the NEXT
BEST opportunity which is ONLY jelly babies
The Economic Way of Thinking: Choosing at the
Margin
 You can allocate the next hour between studying and
emailing your friends. You must decide how many
minutes to allocate to each activity. you compare the
benefits of a little bit more study time with its cost 
you make your choice at the margin.
 The benefit that arises from the increase in the
activity is called marginal benefit.
 The cost of an increase in an activity is called
marginal cost.
The Economic Way of Thinking: Responding to
Incentives
 Our choices respond to incentives.
 For any activity, if marginal benefit exceeds marginal
cost, people have an incentive to do more of that
activity.
 If marginal cost exceeds marginal benefit, people
have an incentive to do less of that activity.
 Incentives are also the key to reconciling self-interest
and the social interest.
The Economic Way of Thinking: Human Nature,
Incentives and Institutions
 Economists take human nature as given and view people
as acting in their self-interest.
 Self-interested actions are not necessarily selfish actions.
 But if human nature is given and people pursue self-
interest, how can the social interest be served?
 Economists answer by emphasizing the role of
institutions in creating incentives to behave in the social
interest.
 Private property protected by a system of laws and
markets that enable voluntary exchange are the
fundamental institutions.
Economics: A Social Science
 Economists distinguish between two types of
statement:
 What ispositive statements
 What ought to benormative statements
 A positive statement can be tested by checking it
against facts.
 A normative statement cannot be tested.
Observation and Measurement
 The first step toward understanding how the
economic world works is to observe it.
 Economists observe and measure data of all aspects
of economic behaviour.
Model Building
 The second step toward understanding how the
economic world works is to build a model.
 An economic model is a description of some aspect of
the economic world that includes only those features
that are needed for the purpose at hand.
Testing Models
 The third step is testing models.
 A models predictions might correspond to the facts
or be in conflict with them.
 A model is tested by comparing its predictions with
the facts
Obstacles and Pitfalls
 Unscrambling cause and effect
 Ceteris Paribus is a Latin term that means other
things being equal.
 By changing one factor at a time and holding all the
other factors constant we isolate the factor of interest
and are able to investigate its effects in the clearest
possible way.

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  • 1. C H A P T E R 1 Economics : What is Economics?
  • 2. Objectives After studying this chapter, you will be able to: Define economics and distinguish between microeconomics and macroeconomics Explain the two big questions of economics Explain the key ideas that define the economic way of thinking Explain how economists go about their work as social scientists
  • 3. Definition of Economics All economic questions arise because we want more than we can get. Our inability to satisfy all our wants is called scarcity. Because we face scarcity, we must make choices. The choices we make depend on the incentives we face. An incentive is a reward that encourages an action or a penalty that discourages an action.
  • 4. Definition of Economics Economics is the social science that studies the choices that individuals, businesses, governments, and entire societies make as they cope with scarcity and the incentives that influence and reconcile those choices. Economics divides in to main parts: Microeconomics Macroeconomics
  • 5. Two Big Economic Questions Two big questions summarize the scope of economics: How do choices end up determining what, how, and for whom goods and services get produced? When do choices made in the pursuit of self- interest also promote the social interest?
  • 6. Two big economic questions: What, How and For whom What? What we produce changes over time What determines the quantities and all the other millions of items that we produce? How? Goods and services are produced by using productive resources that economists call factors of production.
  • 7. How? continues.. Factors of production are grouped into four categories: - Land - Labour - Capital -Entrepreneurship
  • 8. How continues.. The gifts of nature that we use to produce goods and services are land. The work time and work effort that people devote to producing goods and services is labour. The quality of labour depends on human capital, which is the knowledge and skill that people obtain from education, on-the-job training, and work experience. The tools, instruments, machines, buildings, and other constructions that businesses use to produce goods and services are capital. The human resource that organises land, labour, and capital is entrepreneurship.
  • 9. Two Big Economic Questions: For Whom? Who gets the goods and services depends on the incomes that people earn. Land earns rent. Labour earns wages. Capital earns interest. Entrepreneurship earns profit.
  • 10. Two Big Economic Questions: When is the Pursuit of Self- Interest in the Social Interest? Every day, 49 million South Africans and 6.6 billion people in the rest of the world, make economic choices that result in What, How, and For Whom goods and services are produced. Do we produce the right things in the right quantities? Do we use our factors of production in the best way? Do the goods and services go to those who benefit most from them?
  • 11. Two Big Economic Questions: When is the Pursuit of Self-Interest in the Social Interest? Continues.. You make choices that are in your self-interest choices that you think are best for you. Choices that are best for society as a whole are said to be in the social interest. An outcome is in the social interest if it uses resources efficiently and distributes goods and services fairly. Is it possible that when each one of us makes choices that are in our self-interest, it also turns out that these choices are also in the social interest?
  • 12. Two Big Economic Questions: When is the Pursuit of Self-Interest in the Social Interest? Continues.. Five topics that generate discussion and that illustrate tension between self-interest and social interest are Privatisation Globalisation HIV/Aids Water storages Unemployment
  • 13. The Economic Way of Thinking: Choices and Trade-offs Because of scarcity we must make choices, we select from the available alternatives. You can think about every choice as a tradeoffan exchangegiving up one thing to get something else. The classic tradeoff is guns versus butter. Guns and butter stand for any pair of goods.
  • 14. The Economic Way of Thinking: What, How and For Whom Trade-offs What Trade-offs What goods and services get produced depends on choices made by each one of us, when governments choose how to spend their tax revenues, and when businesses choose what to produce. How Trade-offs How goods and services get produced depends on choices made by the businesses that produce them.
  • 15. The Economic Way of Thinking: What, How and For Whom Trade-offs Continues.. For Whom Trade-offs For whom goods and services are produced depends on the distribution of buying power. Government redistribution of income from the rich to the poor creates the big tradeoff - the tradeoff between equality and efficiency.
  • 16. The Economic Way of Thinking: Choices Bring Change The quantity and range of goods and services available today in the US are much greater than those in Africa. The Economic condition of the world today is much better than it was a generation ago. The quality of economic life depends on many of the choices made by each one of us and these choices involve trade-off.
  • 17. The Economic Way of Thinking: Choices Bring Change Continues.. One choice is that of how much of our income to consume and how much to save. If we save more, we can buy more capital and increase our production. A second choice is how much effort to devote to education and training. If we take less leisure time, we can educate and train ourselves to become more productive. A third choice is how much effort to devote to research and development of new products and production methods. If businesses produce less and devote resources to research and developing new technologies, they can produce more in the future
  • 18. The Economic Way of Thinking: Opportunity Cost The opportunity cost of something is the highest- valued alternative that we give up to get it. In other words it is the value of the NEXT BEST opportunity that is sacrificed by the exercise of a choice For instance if you have three items in front of you, namely: a chocolate, a toffee and jelly babies. Arrange these items according to you preference (what you like most to what you like least). Example chocolate, jelly babies and toffee. Chocolate is your first choice hence you will sacrifice the NEXT BEST opportunity which is ONLY jelly babies
  • 19. The Economic Way of Thinking: Choosing at the Margin You can allocate the next hour between studying and emailing your friends. You must decide how many minutes to allocate to each activity. you compare the benefits of a little bit more study time with its cost you make your choice at the margin. The benefit that arises from the increase in the activity is called marginal benefit. The cost of an increase in an activity is called marginal cost.
  • 20. The Economic Way of Thinking: Responding to Incentives Our choices respond to incentives. For any activity, if marginal benefit exceeds marginal cost, people have an incentive to do more of that activity. If marginal cost exceeds marginal benefit, people have an incentive to do less of that activity. Incentives are also the key to reconciling self-interest and the social interest.
  • 21. The Economic Way of Thinking: Human Nature, Incentives and Institutions Economists take human nature as given and view people as acting in their self-interest. Self-interested actions are not necessarily selfish actions. But if human nature is given and people pursue self- interest, how can the social interest be served? Economists answer by emphasizing the role of institutions in creating incentives to behave in the social interest. Private property protected by a system of laws and markets that enable voluntary exchange are the fundamental institutions.
  • 22. Economics: A Social Science Economists distinguish between two types of statement: What ispositive statements What ought to benormative statements A positive statement can be tested by checking it against facts. A normative statement cannot be tested.
  • 23. Observation and Measurement The first step toward understanding how the economic world works is to observe it. Economists observe and measure data of all aspects of economic behaviour.
  • 24. Model Building The second step toward understanding how the economic world works is to build a model. An economic model is a description of some aspect of the economic world that includes only those features that are needed for the purpose at hand.
  • 25. Testing Models The third step is testing models. A models predictions might correspond to the facts or be in conflict with them. A model is tested by comparing its predictions with the facts
  • 26. Obstacles and Pitfalls Unscrambling cause and effect Ceteris Paribus is a Latin term that means other things being equal. By changing one factor at a time and holding all the other factors constant we isolate the factor of interest and are able to investigate its effects in the clearest possible way.