Critical Thinking Course Overview: Part I Units Explained

Critical Thinking Course Overview: Part I Units Explained for University of Ghana ICDE Students

Are you studying Critical Thinking with the Institute of Continuing and Distance Education (ICDE) at the University of Ghana, Legon? Then you have probably opened your course book and seen the Part I overview. It looks short. But it hides a lot of useful learning.

This guide walks you through every unit and section in Part I. You will see what each topic means, why it matters, and how to study it well.

Think of this post as your friendly map. By the end, you will know where you are going before you take the first step.

In this guide

• What is critical thinking?
• Part I at a glance
• Unit 1: Thoughts as Objects of Scrutiny
• Unit 2: Definitions
• Unit 3: Contrasting Types of Discourse
• Why this course matters
• A simple study plan
• Common mistakes to avoid
• Frequently asked questions

What Is Critical Thinking?

Critical thinking is the habit of examining ideas before accepting them. It means asking what a claim says, what supports it, and whether the reasoning holds up.

It is not the same as criticising people. It is also not about being negative. It is about being careful, fair and clear.

Every day, you receive claims. Some come from lecturers and textbooks. Others come from radio, WhatsApp groups, church announcements, political rallies and social media. A critical thinker does not swallow all of them. A critical thinker sorts them.

Part I of your course trains this skill from the ground up. It begins with the smallest building block, which is a single thought expressed in a sentence. Then it moves to words and their meanings. Finally, it looks at whole passages and how people argue.

Part I at a Glance

Part I has three units. Each one has an introduction, several sections and a unit summary. Units 2 and 3 also include assignments.

• Unit 1: Thoughts as Objects of Scrutiny (3 sections)
• Unit 2: Definitions (4 sections plus Assignment 2)
• Unit 3: Contrasting Types of Discourse (4 sections plus Assignment 3)

The order is deliberate. You first learn to identify thoughts. Then you learn to define the words inside them. Then you learn to spot problems in how people use language to argue.

Skip one stage, and the next becomes harder. So take them in order.

Unit 1: Thoughts as Objects of Scrutiny

What Does "Thoughts as Objects of Scrutiny" Mean?

Normally, we use our thoughts to look at the world. In this unit, you turn the lens around. You look at the thoughts themselves.

Scrutiny simply means close examination. So the unit asks you to treat a thought like a specimen on a lab table. What kind is it? Is it complete? Can it be tested?

Most thoughts reach us in the form of sentences. That is why the unit focuses on "sentence-shaped" thought. A sentence is the container, and the thought is what sits inside.

Before you can judge whether a thought is good or bad, you must first know what sort of thought it is. That is the whole purpose of Unit 1.

Section 1: Distinguishing Types of Sentence-Shaped Thought

Not all sentences do the same job. This is the first big lesson of the course.

Consider these four examples:

• "Accra is the capital of Ghana."
• "Is Accra the capital of Ghana?"
• "Please travel to Accra."
• "What a busy city Accra is!"

All four mention Accra. Yet each does something different. The first states a fact. The second asks a question. The third gives a request or command. The fourth expresses a feeling.

Grammar books name these types declarative, interrogative, imperative and exclamatory. Your course may use its own labels, so always follow the terms in your course book.

Why does this matter? Because only some of these sentences can be true or false. If someone says "Close the door," you cannot reply, "That is false." A command is not the kind of thing that is true or false.

This simple point prevents many confused arguments. People often attack a question as if it were a claim. Or they treat a command as if it were a statement of fact.

Here is a quick test you can use:

1. Read the sentence.
2. Ask yourself: "Can this be true or false?"
3. If yes, it is likely a statement. If no, identify what else it is doing.

Notice also that sentences can be disguised. "Wouldn't you agree that fuel prices are too high?" looks like a question. But it quietly pushes a claim. A sharp reader spots the claim hiding inside.

Study tip: Collect ten sentences from a newspaper. Label each one. Then check whether any of them are doing a second job in disguise.

Section 2: Recognising Sentence Fragments and Expressions of Feeling

Some groups of words look like sentences but are not complete thoughts. These are fragments.

Take the phrase "Because the lecturer arrived late." It leaves you waiting. Because of that, what happened? The thought is unfinished.

Compare it with "The class started late because the lecturer arrived late." Now the thought is complete. You can agree or disagree with it.

Why does this matter in critical thinking? You cannot evaluate half a thought. A fragment gives you nothing to test.

Fragments appear everywhere. They show up in adverts, headlines and slogans. "Fresh. Natural. Affordable." These words create an impression, but they do not say anything you can check.

The second half of this section deals with expressions of feeling. Examples include "Ouch!", "Wow!" and "Yuck!"

These are reactions. They show how someone feels. They do not describe the world in a way that can be proven right or wrong.

Be careful here, though. Sometimes a feeling is mixed with a claim. "This food is disgusting" expresses feeling, but it may also suggest that the food is of poor quality. You must learn to separate the two parts.

Here is why this separation is useful:

• The feeling part cannot be argued with in the same way as a factual claim.
• The claim part can be examined and tested.
• Mixing them up leads to pointless debates.

If a friend says, "I hate that film," you cannot prove them wrong about their feeling. But if they add, "It is the worst film ever made," that is a claim you can question.

Section 3: Identifying Different Types of Declarative Statement

Once you know which sentences can be true or false, you meet a new question. Are all of these statements the same?

The answer is no. Declarative statements come in different types, and each type is tested differently.

Here are some of the kinds you will commonly meet:

• Factual (descriptive) statements. "Lake Volta is in Ghana." You test these by checking the evidence.
• Evaluative statements. "Honesty is better than deceit." These express judgements of value.
• Prescriptive statements. "Students ought to submit assignments on time." These say what should be done.
• Definitional statements. "A bachelor is an unmarried man." These are true because of meaning.

Your course book may group or name them differently. The key skill is the same. Know what type of statement you are looking at before you decide how to test it.

Why does this matter? Because using the wrong test wastes time. You cannot settle a question of value by measuring something with a ruler. And you cannot settle a question of fact by simply stating your opinion louder.

Many heated arguments happen because people mix these types. One person offers a fact. The other responds with a value judgement. Neither realises they are talking past each other.

Try this example. Someone says, "Public transport in the city is poor, so the government must act." The first half is a factual claim. The second half is a prescription. Each needs separate support.

A good critical thinker breaks the sentence apart and checks each piece on its own terms.

Unit 1 Summary: What You Should Take Away

By the end of Unit 1, you should be able to:

• Tell apart statements, questions, commands and expressions of feeling.
• Recognise incomplete sentences that cannot be judged.
• Separate feeling from claim in everyday speech.
• Identify the main types of declarative statement.

These skills may feel basic. But everything else in the course rests on them.

Unit 2: Definitions

Why Definitions Matter So Much

Imagine two people arguing about whether a certain job is "skilled work." One thinks it requires a degree. The other thinks it only requires experience. They may argue for hours without noticing they are using the word differently.

That is the problem Unit 2 tackles. When the meaning of a word is unclear, thinking becomes unclear.

Definitions are the tools we use to fix meaning. A good definition clears the fog. A poor one makes it thicker.

This unit teaches you how definitions work, what makes them strong, where the tricky cases lie, and how to diagnose faults.

Section 1: Types of Definition

There is more than one way to define a word. Different situations call for different kinds of definition.

Here are the common types that critical thinking courses discuss:

• Lexical definitions. These report how a word is actually used. Dictionaries mostly give lexical definitions.
• Stipulative definitions. Here, you decide what a word will mean for a particular purpose. "In this report, 'student' means anyone enrolled in a degree programme."
• Precising definitions. These sharpen a vague word. A rule might say "adult" means anyone aged eighteen or above.
• Theoretical definitions. These explain a term within a theory or field of study.
• Persuasive definitions. These try to shape your attitude through the way a word is defined. They are used to influence, not just inform.
• Ostensive definitions. These define by pointing. "That is what I mean by a kente cloth."

Each type serves a different purpose. A lexical definition helps you understand what others mean. A stipulative definition helps you set clear rules for a discussion.

The persuasive kind deserves special care. Suppose someone says, "Freedom is the right to do whatever benefits the nation." That sounds like a definition. But it is really an argument wearing a definition's clothes.

You will also meet the ideas of extension and intension. The extension of a term is the set of things it applies to. The intension is the set of qualities that make something count.

For example, the extension of "region of Ghana" is the list of regions. The intension is what makes an area qualify as a region.

Knowing these types helps you do two things. First, you can choose the right kind when you write your own definitions. Second, you can recognise what others are doing when they define a term.

Study tip: Take five words, such as "democracy," "success," "education," "poverty" and "leader." Write one lexical, one stipulative and one persuasive definition for each.

Section 2: Well Defined Terms

What makes a definition good? This section answers that question.

A well defined term has clear boundaries. You can tell what falls inside the term and what falls outside.

Take the word "triangle." It is defined as a closed shape with three straight sides. Anyone can check any shape against this rule. That makes "triangle" a well defined term.

The idea behind this is often explained through conditions. A necessary condition is something that must be present. A sufficient condition is something that is enough on its own.

Good definitions try to capture both. They list what is needed and make sure nothing extra sneaks in.

Common standards for a good definition include these:

1. It should not be too broad. If you define "car" as "a vehicle," you include buses, bicycles and trains.
2. It should not be too narrow. If you define "car" as "a four-door vehicle," you leave out two-door cars.
3. It should not be circular. "A teacher is someone who teaches" tells you nothing new.
4. It should be clear. Using harder words than the word being defined defeats the purpose.
5. It should not rely on figures of speech. "Time is a thief" is poetic but not a definition.

A common method is to name the broader group and then explain what sets the item apart. A "stool" is a seat (the broader group) without a back or arms (what sets it apart).

Notice how this approach feels natural. It is how people explain things to children and to visitors from other places.

Well defined terms matter because they make discussion productive. When everyone uses a word the same way, you can argue about real issues instead of confusion.

Section 3: Open Class Concepts

Here is where things get interesting. Not every concept can be pinned down with a neat definition.

Some concepts are open. This means new members can keep joining, and the edges stay fuzzy. We cannot list a fixed set of conditions that every member must meet.

The classic example is the idea of a "game." Football is a game. So is chess. So is ludo. So is a child playing with a ball alone.

Try to find one feature that all games share. Competition? Not in solo play. Winning and losing? Not in every case. Equipment? Not always.

Instead, games seem to share overlapping similarities, like members of a family. One may share your nose, another your smile, and no single feature is common to all. This idea is often called family resemblance.

Other examples include "art," "music," "sport," "education" and "religion." New things keep appearing that challenge the old boundaries. Is a video game a sport? Is a digital painting art? People still debate these questions.

What is the lesson here? A critical thinker does not force every concept into a tight box. Doing so can lead to silly results.

But the lesson goes both ways. Open concepts do not mean "anything goes." There are clear cases and clear non-cases. A brick is not a game. A rock is not a song.

The fuzzy zone lies in the middle. And when you notice that a debate sits in that zone, you can say so. You can stop demanding a single decisive definition and instead discuss which features matter for the purpose at hand.

This section protects you from two mistakes. One is demanding perfect definitions where none exist. The other is claiming that because a term is fuzzy, it means nothing at all.

Section 4: Diagnosing Problems with Definitions

Now you put your knowledge to work. This section trains you to examine a definition and say what is wrong with it.

Think of yourself as a doctor for definitions. You look at the symptoms, name the problem and suggest a fix.

Here are the typical problems:

Too Broad

The definition covers things it should not. "A student is a person who learns." By this rule, everyone who has ever learned anything counts as a student.

Too Narrow

The definition leaves out things it should include. "A farmer is someone who grows cocoa." This leaves out maize farmers, rice farmers and vegetable growers.

Circular

The definition uses the word itself, or a close relative. "Honesty is the quality of being honest."

Obscure or Vague

The definition uses language that is harder to understand than the original. "A cat is a quadruped feline carnivore of domesticated disposition."

Figurative

The definition relies on metaphor. "Education is the light of the nation." Lovely, but it does not tell you what education is.

Loaded or Biased

The definition sneaks in an opinion. "A politician is a person who lies for a living."

Once you have spotted the fault, the next step is to repair it. A good answer in an exam does both. It names the problem and offers a better version.

Let us practise with one example. Suppose a definition says, "A book is something you read." What is wrong?

It is too broad. You can read a road sign, a face or

Critical Thinking Course Overview: Parts II and III Explained for University of Ghana ICDE Students

You have finished Part I of your Critical Thinking course. You can now spot different kinds of sentences, handle definitions with care, and recognise how language misleads. Good work.

Now the course moves on. Parts II and III take you from words and sentences to the big picture of knowledge itself, and then to the heart of reasoning: deduction and induction.

This guide is written for students of the Institute of Continuing and Distance Education (ICDE) at the University of Ghana, Legon. It walks you through Units 4, 5 and 6, section by section. You will see what each topic means, why it matters and how to study it.

If you missed the earlier post, it covers Part I: Units 1 to 3. Read that first if you can. The skills build on each other.

In this guide

• Parts II and III at a glance
• Part II: Knowledge, facts and values
• Unit 4: Surveying the Map of Knowledge
• Unit 5: The Normative and the Empirical
• Part III: Reasoning
• Unit 6: Deduction vs. Induction
• Why these skills matter
• A simple study plan
• Common mistakes to avoid
• Frequently asked questions

Parts II and III at a Glance

Here is the layout of the next stage of the course.

• Part II, Unit 4: Surveying the Map of Knowledge (4 sections plus Assignment 4)
• Part II, Unit 5: The Normative and the Empirical (3 sections plus Assignment 5)
• Part III, Unit 6: Deduction vs. Induction (5 sections plus Assignment 6)

Each unit begins with an introduction and ends with a unit summary. Between them come the sections and the assignment.

Notice the shape of the journey. Part II asks: what kinds of knowledge exist, and what kinds of claims do we make? Part III then asks: how do we reason from one claim to another?

First you learn what you are dealing with. Then you learn how to work with it. That order makes sense, and it is worth following.

A quick note: Your course book is the official source. Where this guide gives examples, lists or labels, always check them against your own materials. Your lecturers may group ideas a little differently.

Part II: Knowledge, Facts and Values

Part II steps back from single sentences and looks at the world of knowledge as a whole.

Think of a map. A map does not show you every tree and house. It shows you the main regions and how they connect. In the same way, Part II gives you a map of human knowledge, so you can see where different subjects sit and how they differ.

Then it turns to a question that causes endless confusion. When someone makes a claim, is it a claim about how things are, or a claim about how things ought to be?

Unit 4: Surveying the Map of Knowledge

What Is This Unit About?

University is divided into faculties, departments and programmes. You may study Arts, Social Sciences, Law, Education or Business. But have you ever asked why knowledge is divided this way?

Unit 4 invites you to survey the whole landscape. You learn how academic disciplines are grouped, how types of knowledge differ, where the social sciences came from, and how they differ from the natural sciences.

Why does this belong in a critical thinking course? Because the way you test a claim depends on the kind of claim it is, and on the kind of subject it comes from. A historian, a chemist and an economist all ask good questions. But they do not all use the same methods.

Section 1: Classifying Academic Disciplines

The first job is sorting. Disciplines can be grouped by what they study and how they study it.

Here is one common way to sort them:

• The natural sciences. These study the physical world. Physics, chemistry, biology and geology are examples.
• The social sciences. These study human society and behaviour. Sociology, economics, political science, psychology and anthropology belong here.
• The humanities. These study human culture, ideas and expression. History, literature, philosophy, languages and religious studies are examples.
• The formal sciences. These study abstract systems. Mathematics and logic are the main examples.
• The applied and professional fields. These use knowledge for practical ends. Medicine, engineering, law, education and agriculture are examples.

Your course book may use a slightly different scheme. Some books combine the formal sciences with the natural sciences. Others treat the applied fields as a separate branch altogether. Follow the version your course gives you.

Here is an important point. These boundaries are not walls. Many fields sit on the border between groups. Psychology has links with biology and with the social sciences. Linguistics touches the humanities, the social sciences and the formal sciences. Geography reaches across several areas.

Why does classification matter? There are several reasons:

1. It helps you understand what a given discipline can and cannot tell you.
2. It helps you pick the right kind of evidence for the right kind of question.
3. It helps you see how different fields can work together.
4. It protects you from silly demands, such as asking a poem to be proven in a laboratory.

Consider the question, "Why do some communities migrate from rural areas to cities?" A geographer, an economist, a sociologist and a historian might each contribute. Each offers a different piece of the answer.

Study tip: Draw a simple map with five circles for the five groups above. Place at least four disciplines in each circle. Then mark any discipline that could sit in more than one place.

Section 2: Contrasting Different Types of Knowledge

The word "knowledge" covers many things. When you say "I know how to swim" and "I know that Accra is in Ghana," you are using the word in different ways.

This section helps you separate the main types.

Knowing That, Knowing How and Knowing by Acquaintance

Knowing that is knowledge of facts. You know that water boils at a certain temperature at sea level. You know that Ghana became independent in 1957. This type can be stated in sentences.

Knowing how is practical skill. You know how to ride a bicycle, cook jollof rice or drive a car. You may struggle to explain it in words, yet you can do it.

Knowing by acquaintance comes from direct experience. You know your hometown, a friend or the taste of fresh coconut water. Reading about these things is not the same as meeting them.

A Priori and A Posteriori Knowledge

Another important split concerns how we come to know something.

A priori knowledge comes from reasoning alone. You do not need to check the world. "All bachelors are unmarried" and "two plus two equals four" are standard examples.

A posteriori knowledge depends on experience and observation. "It rained in Kumasi yesterday" can only be known by checking the world.

Empirical and Non-Empirical Knowledge

Empirical knowledge rests on observation and evidence. Most of the natural and social sciences work this way. Non-empirical knowledge, such as that of pure mathematics and logic, rests on reasoning and definitions.

Other Contrasts You May Meet

Depending on your course book, you may also see these contrasts:

• Theoretical and practical knowledge. Understanding why something works versus knowing how to apply it.
• Common-sense and scientific knowledge. Everyday beliefs versus claims tested by careful method.
• Traditional and modern knowledge. Knowledge handed down through generations versus knowledge produced by formal research. Both can hold real value, and both deserve careful, fair examination.
• Knowledge and mere belief. A belief can be strong and still be false. Knowledge usually requires that the belief be true and well supported.

The last point deserves attention. Philosophers often say that knowledge requires at least three things: you must believe something, it must be true, and you must have good reasons. Having a strong feeling is not enough.

Why does all this matter? Because when someone says "I know," you can ask: what kind of knowing is it? How did you come to know it? What would count as evidence?

A farmer who "knows" when the rains will come through years of experience has real knowledge. A weather scientist who "knows" it through satellite data also has real knowledge. These are different routes. A critical thinker respects both but asks how each is supported.

Section 3: Historical Development of Social Science

Where did the social sciences come from? This section tells the story.

People have always thought about society. Ancient thinkers discussed government, justice and human nature. African oral traditions preserved reflection on community, leadership and law. But the social sciences as organised academic fields are fairly recent.

The Early Roots

Long before universities, thinkers wrote about how to rule well and how to live together. These early efforts were mixed with philosophy, religion and storytelling. There was no clear line between "science" and "wisdom."

The Age of Enlightenment

In Europe, the seventeenth and eighteenth centuries brought a new confidence in reason and observation. The success of the natural sciences inspired a bold question. Could society be studied with the same careful methods?

Early writers on economics, politics and human nature began to examine society more systematically. This laid the groundwork for later fields.

The Nineteenth Century: Fields Take Shape

In the nineteenth century, separate social sciences began to emerge. Sociology was named and developed as a field, with thinkers such as Auguste Comte, Emile Durkheim, Karl Marx and Max Weber shaping it. Economics grew into a formal discipline. Psychology moved into the laboratory in the late nineteenth century. Anthropology expanded through the study of cultures around the world.

Industrialisation, the growth of cities and rapid social change gave these fields urgent questions. Why do societies change? What causes poverty? How do institutions work?

The Twentieth Century and After

In the twentieth century, the social sciences spread to universities worldwide. Research methods improved. Surveys, statistics and field studies became common. Fields such as political science, development studies and communication studies grew.

Many of these developments also faced fair criticism. Scholars from Africa, Asia and Latin America pointed out that early social science often reflected the views and assumptions of a small part of the world. Colonial-era studies sometimes described other peoples in biased ways. Today, there is a stronger push for research that includes local knowledge and local voices.

Why Does the History Matter?

Knowing the history helps you do three things:

• Understand that disciplines are human creations that grow and change.
• Notice that theories can carry the assumptions of their time and place.
• Appreciate why debates about method continue today.

A critical thinker asks not only "What does this theory say?" but also "Who developed it, when, and for what purpose?"

Dates and names may appear in your course book. Learn the ones it emphasises. In exams, a clear outline of the main stages, with a few well-chosen examples, is usually better than a long list of names without explanation.

Section 4: Distinguishing Social Studies from Natural Sciences

The last section of Unit 4 asks a tricky question. If the social sciences study society using careful methods, are they the same as the natural sciences? The usual answer is: they share a lot, but important differences remain.

The section title in your course book may be cut off in some copies. It deals with the contrast between the social studies (or social sciences) and the natural sciences. Let us look at the common points of difference.

1. The Subject Matter Can Think and Choose

A rock does not read what scientists write about it. People do. Humans have beliefs, intentions, emotions and the ability to choose. This makes human behaviour harder to predict than the fall of a stone.

2. People React to Being Studied

When people know they are being observed, they may change how they act. Researchers have to think about this carefully. Chemicals in a test tube do not behave differently because someone is watching.

3. Controlled Experiments Are Harder

In a laboratory, a chemist can control temperature, pressure and ingredients. A sociologist cannot place a whole community in a laboratory. For ethical and practical reasons, many social questions cannot be tested through tight experiments.

4. Many Causes Work Together

Social events usually have many causes at once. Why did a business fail? Poor management, a weak economy, bad location and changing tastes may all play a part. It is difficult to isolate one cause.

5. Values Are Closer to the Surface

Social questions often touch on fairness, rights and welfare. Researchers may find it harder to keep their own values out. Good researchers try to be open about their assumptions.

6. Context Matters a Great Deal

A finding in one society may not hold in another. Culture, history and local conditions shape behaviour. The laws of physics do not change from Accra to Tokyo, but social patterns can.

What the Two Have in Common

It would be wrong to say the social sciences are "not real science." They share important features with the natural sciences:

• Both aim to explain things using evidence.
• Both use careful observation and testing.
• Both welcome criticism and correction.
• Both build theories that can be revised.

The differences are mostly about degree and difficulty, not about whether careful thinking is possible. A critical thinker avoids two extremes. One extreme says social science is just opinion. The other says it should copy physics exactly.

Assignment 4: Mapping Knowledge

Assignment 4 comes at the end of Unit 4. Expect tasks that ask you to classify disciplines, contrast types of knowledge, outline the development of social science, or compare social and natural sciences.

To prepare:

1. Re-read all four sections slowly.
2. Make a one-page comparison table: social sciences on one side, natural sciences on the other.
3. Write one example for each type of knowledge.
4. Practise explaining the history of social science in five or six sentences.
5. Give reasons for every claim. Do not just list.

Unit 4 Summary: What You Should Take Away

By the end of Unit 4, you should be able to:

• Sort academic disciplines into major groups and explain the overlaps.
• Contrast the main types of knowledge.
• Outline how the social sciences developed over time.
• Explain how the social and natural sciences are alike and different.

Unit 5: The Normative and the Empirical

What Do These Two Words Mean?

These words sound heavy. Their meanings are simple.

Empirical statements are about how things are. They describe the world as we can observe it. "Ghana has ten regions" or "this road is flooded" are empirical claims, whether they turn out true or false.

Normative statements are about how things ought to be. They set standards, give rules or make value judgements. "Corruption is wrong" and "drivers should obey traffic lights" are normative claims.

Why does this split matter? Because the two kinds of claim are supported in different ways. You settle an empirical claim by checking evidence. You settle a normative claim by thinking about values, principles and consequences.

Mixing them up causes many confused debates. Unit 5 helps you untangle them.

Section 1: Six Senses of "Law"

The word "law" is a perfect example of a slippery term. It is used in many ways