Critical Thinking

Here you will find some references and articles explaining the practical methods of critical thinking

First, here are the basics of Critical Thinking summerised from the two popular books listed in the critical thinking books page.


Here are the 3 forms of logical argument that can be used to draw rational conclusions (P=premise/fact ; C=conclusion):

What is a “good” argument?

Socrates 469 BC – 399 BC

A “good” argument has ALL true premises.

A)    Deductive Arguments
P1     All men are mortal
P2     Socrates is a man
C       Socrates is mortal

B) Inductive Arguments
P1   If Socrates is a man, then he is most likely mortal
P2   Socrates is a man.
C     Socrates is probably mortal.

C)  Plausible Arguments
P1   Ms A is a genuine expert about man’s mortality
P2   Ms A proposes that Socrates is mortal
P3   Socrates is a man.
P4   That “Socrates is mortal” is consistent with what other experts propose.
P5  “Socrates is mortal” is consistent with the available evidence.
C    “Socrates is mortal” can be accepted as a plausible argument.


The “State of our Planet” is not often presented ín the press like a sunfilled tropical beach.

Life Is A Beach

But almost every day The Media (newspapers and TV) warn of coming catastrophes, treating us like a big dirty city, at night, under a terrible thunderstorm.

How The Media often portay our world.

Critical thinking is essential if you want to be a person who “pans for the gold nuggets of truth” about our world, rather that being a sponge sucking up anything that is said.

Here are also some .pdf slides describing the critical thinking process: Critical Thinking 1, Critical Thinking 2, Critical Thinking 3, Critical Thinking 4 and Critical Thinking 5 .


Second, here are a list argumental fallacies to avoid using in the 3 logical argument structures:

Protagoras the Sophist 490 BC – 420 BC (the first to list fallacies of argument)

Argumental Fallacies

1. Unacceptable – premises are at least as dubious as the claims they are supposed to support.
a) Begging the Question
The conclusion is used as one of the premisses.
b) False Dilemma
Assumes only two alternatives exist.

2. Irrelevant – premises have no bearing on the truth of the conclusion.
a) Equivocation
A word is used in two different senses in an argument.
b) Composition
Claims that what is true of the parts is also true of the whole.
c) Division
Assumes that what is true of a whole is also true of it’s parts.
d) Appeal to the Person
Tries to rebut an argument by criticising it’s presenter (ad hominem).
e) Genetic Fallacy
Argues that a claim’s truth or falsity depends on its origin.
f) Appeal to Authority
Argues that an authority/expert is infallible so evidence isn’t needed.
g) Appeal to the Masses
Argues that a lot of people believe something so it must be true.
h) Appeal to Tradition
Argues that people have always done so therefore it must be true.
i) Appeal to Ignorance
Takes a lack of evidence for one thing as being good evidence for another.
j) Appeal to Fear
Uses the threat of harm to advance one’s position.

3. Insufficient- premises do not establish a conclusion beyond reasonable doubt.
a) Hasty Generalisation
Generalises about an entire class of things from observing only one.
b) Faulty Analogy
Claims that things that resemble one another in some respects resemble each other in other respects.
c) False Cause
Supposes that two events are causally connected just because one happens with the other.


Asking the Right Questions: A Guide to Critical Thinking, 9th Edition

Thirdly, here is a link to the book above giving exercises with answers to common critical thinking problems.


Here are some examples of crticial thinking questions, about Science in the Media , that can be given to students.

Here is an (Nov 2011) example of critical thinking about Arctic Ice building from the new Swedish school curriculum Lgr11. Another about Ozone and references. About Acid Rain (with Forest Death questions) and Stranger Danger. And a final about our friend CO2  🙂

Here are the Critical Thinking Basics that can be taught to lower secondary school (middle school) students. And a Swedish discussion about: Cap on or off – teaching dilemma .

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