1. SCIENTIFIC REASONING & CRITICAL THINKING
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Critical thinking is the ability to think clearly
and rationally. It includes the ability to engage
in reflective and independent thinking. Someone
with critical thinking skills is able to do the
following :
understand the logical connections
between ideas
identify, construct and evaluate
arguments
detect inconsistencies and common
mistakes in reasoning
solve problems systematically
identify the relevance and importance of
ideas
reflect on the justification of one's own
beliefs and values
Critical thinking is not a matter of accumulating
information. A person with a good memory and
who knows a lot of facts is not necessarily good
at critical thinking. A critical thinker is able to
deduce consequences from what he knows, and
he knows how to make use of information to
solve problems, and to seek relevant sources of
information to inform himself or herself.
Critical thinking should not be confused with
being argumentative or being critical of other
people. Although critical thinking skills can be
used in exposing fallacies and bad reasoning,
critical thinking can also play an important role in
cooperative reasoning and constructive tasks.
Critical thinking can help us acquire knowledge,
improve our theories, and strengthen
arguments. We can use critical thinking to
enhance work processes and improve social
institutions.
Some people believe that critical thinking
hinders creativity because it requires following
the rules of logic and rationality, but creativity
might require breaking rules. This is a
misconception. Critical thinking is quite
compatible with thinking "out-of-the-box",
challenging consensus and pursuing less
popular approaches. If anything, critical thinking
is an essential part of creativity because we
need critical thinking to evaluate and improve
our creative ideas.
How to improve
Critical thinking is a meta-thinking skill. It
requires thinking about thinking. We have to
reflect on the good principles of reasoning and
make a conscious effort to internalize them and
apply them in daily life. This is notoriously hard
to do and often requires a long period of
training. The mastery of critical thinking is
similar to the mastery of many other skills.
There are three important components: theory,
practice, and attitude.
§ C04.1 Theory
§ C04.2 Practice
§ C04.3 Attitudes
Good critical thinking skills require not just
knowledge and practice. Persistent practice can
bring about improvements only if one has the right
kind of motivation and attitude. The following
attitudes are not uncommon, but they will not help
you improve your thinking:
- I prefer being given the correct answers
rather than figuring them out myself.
- I don't like to think a lot about my
decisions as I rely only on gut feelings.
- I don't usually review the mistakes I
have made.
- I don't like to be criticized.
What is logic? A preliminary definition
The term "logic" came from the Greek
word logos, which is sometimes translated as
"sentence", "discourse", "reason", "rule", and
"ratio". Of course, these translations are not
enough to help us understand the more
specialized meaning of "logic" as it is used
today.
So what is logic? Briefly speaking, we might
define logic as the study of the principles of
correct reasoning. This is a rough definition,

2. SCIENTIFIC REASONING & CRITICAL THINKING
cariejustine_estrellado@yahoo.com
because how logic should be properly defined is
actually quite a controversial matter.
How is science different from logic?
- Science does involve logic, since we
need logic to test our theories and
check whether they are consistent. But
for a theory to be a scientific one, it
must either describe actual empirical
facts about the world or the laws of
nature in our universe. This is not the
case with logic.
How is mathematics different from logic?
- The relationship between mathematics
and logic is rather complicated
philosophical issue. To give a very short
answer, the content of mathematics is
restricted to abstract objects like
numbers, functions, triangles, etc. But
the principles and laws of logic are very
general and are not restricted to such
concepts.
What is a statement?
There are three main sentence types in English:
Declarative sentences are used for
assertions, e.g. "He is here."
Interrogative sentences are used to ask
questions, e.g. "Is he here?"
Imperative sentences are used for
making requests or issuing commands,
e.g. "Come here!"
For present purposes, we shall take a statement
to be any declarative sentence. A declarative
sentence is a complete and grammatical
sentence that makes a claim.
Snow is white.
The moon is made of green cheese.
Everyone is here.
Whatever will be, will be.
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As you can see, statements can be true or false,
and they can be simple or complex. But they
must be grammatical and complete sentences.
So these are not statements :
The United Nations [ A proper name, but
not a sentence ]
Bridge over troubled waters. [ Not a
complete sentence ]
Come here right now! [ A command that
is not a complete sentence making a
claim ]
Will you be available on Tuesday or
Wednesday? [ A question ]
HJGAS&*^@#JHGKJAS*&^*!@GJHGA
A*&S [ Ungrammatical ]
Exercise 1 identify if the ffg. Whether it is a
statement or not.
1. One plus one equals three.
2. Can you come to the party please?
3. AJH$%^#@!
4. If it rains then the street will be wet.
5. We all feel very sorry for you.
6. Come here!
7. A chicken is a song that weighs ten
tons.
8. All statements are true.
9. It is true that it is raining
10. I am ordering you to stop talking in
class.
Exercise 2 Rewrite these utterances or
headlines as statements.
1. Inflation rising.
2. Kidnapper : no ransom, boy dies
3. Scientists : coffee good for health
4. Paintings stolen from Presidential
Palace.
5. No money, I no work.

3. SCIENTIFIC REASONING & CRITICAL THINKING
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Argument – any group of propositions of which one is claimed to follow logically from the
others.
Central Parts of an argument
a. Premiss: (more usually spelled "premise") a proposition which gives reasons, grounds, or
evidence for accepting some other proposition, called the conclusion.
b. Conclusion: a proposition, which is purported to be established on the basis of other
propositions.
In everyday life, people often use "argument" to mean a quarrel between people. But in logic and critical
thinking, an argument is a list of statements, one of which is the conclusion and the others are
the premises or assumptions of the argument.
To give an argument is to provide a set of premises as reasons for accepting the conclusion. To give an
argument is not necessarily to attack or criticize someone. Arguments can also be used to support other
people's viewpoints.
Here is an example of an argument:
If you want to find a good job, you should work hard. You do want to find a good job. So you
should work hard.
I played DOTA all the way yesterday even without reviewing my notes since I got the highest
score in my exam today, so playing games would be better help to improve my grades.
Exercise 3
See if you can give arguments to support some of your beliefs.
- Do you think the economy is going to improve or worsen in the next six months? Why or why not?
What arguments can you give to support your position?
- Or think about something different, do you think computers can have emotions? Again, what
arguments can you give to support your viewpoint? Make sure that your arguments are
composed of statements.
Exercise 4
Do these passages contain argument? What are their conclusions?
1. Cutting the interest rate will have no effect on the stock market this time round as people have
been expecting a rate cut all along. This factor has already been reflected in the market.
2. So it is raining heavily and this building might collapse. But I don't really care.
3. Virgin would then dominate the rail system. Is that something the government should worry
about? Not necessarily. The industry is regulated, and one powerful company might at least offer
a more coherent schedule of services than the present arrangement has produced. The reason
the industry was broken up into more than 100 companies at privatization was not operational,
but political: the Conservative government thought it would thus be harder to renationalize. The
Economist 16.12.2000
4. Bill will pay the ransom. After all, he loves his wife and children and would do everything to save
them.

4. SCIENTIFIC REASONING & CRITICAL THINKING
cariejustine_estrellado@yahoo.com
How to look for arguments
How do we identify arguments in real life? There are no easy mechanical rules, and we usually
have to rely on the context in order to determine which are the premises and the conclusions.
But sometimes the job can be made easier by the presence of certain premise or conclusion
indicators. For example, if a person makes a statement, and then adds "this is because ...", then
it is quite likely that the first statement is presented as a conclusion, supported by the
statements that come afterwards. Other words in English that might be used to indicate the
premises to follow include :
since
firstly, secondly, ...
for, as, after all,
assuming that, in view of the fact that
follows from, as shown / indicated by
may be inferred / deduced / derived from
Of course whether such words are used to indicate premises or not depends on the context. For
example, "since" has a very different function in a statement like "I have been here since noon",
unlike "X is an even number since X is divisible by 4".
Conclusions, on the other hand, are often preceded by words like:
therefore, so, it follows that
hence, consequently
suggests / proves / demonstrates that
entails, implies