5. • Relevance is the concept of
one topic being connected to
another topic in a way that
makes it useful to consider the
second topic when considering
the first.
6. •Soundness is a technical term in logic. It is
used to describe arguments whose forms
are valid and whose premises are true. A
valid argument form is one whose
premises and conclusions is arranged
such that truth in the premises is
ineluctably transferred to the conclusion.
Therefore, a sound argument must have a
true conclusion.
7. •Premise - a previous statement or
proposition from which another is inferred
or follows as a conclusion.
•Conclusion - Logical result of the
relationship between the premises.
Conclusions serve as the thesis of the
argument.
8. WHAT IS AN ARGUMENT?
• In the field of logic and philosophy, an argument is a series of
statements intended to determine the degree of truth of another
statement. Premises and conclusions are the building blocks of an
argument. Premises are a series of statements that provide
reasons or evidence to determine the truth of a conclusion.
Therefore, an argument can have more than one premise. A
conclusion in an argument is the main point the arguer is trying to
prove. Thus, an argument has only one conclusion and one or
more premises.
9. WHAT IS LOGIC?
•Logic is reasoning conducted or assessed
according to strict principles of validity.
10. WHAT IS PHILOSOPHY?
•Philosophy is the study of the fundamental
nature of knowledge, reality, and existence,
especially when considered as an academic
discipline.
11. WHAT IS AN ARGUMENT?
• In the field of logic and philosophy, an argument is a series of
statements intended to determine the degree of truth of another
statement. Premises and conclusions are the building blocks of an
argument. Premises are a series of statements that provide
reasons or evidence to determine the truth of a conclusion.
Therefore, an argument can have more than one premise. A
conclusion in an argument is the main point the arguer is trying to
prove. Thus, an argument has only one conclusion and one or
more premises. Let’s look at an example:
12. EXAMPLE
•Premise 1: No one under eighteen-years-old
can vote.
•Premise 2: Rogan is under eighteen.
•Conclusion: Therefore, Rogan cannot vote.
13. WHAT IS A SOUND ARGUMENT?
• An argument must fulfill two requirements in order to be
considered as sound. One requirement is that the argument
must be valid. An argument is valid when its conclusion
follows logically from the premises. In other words, it is
impossible for the premises of an argument to be true while
the conclusion is false. The second requirement is that all its
premises should be true. Thus, a sound argument is a valid
argument that has true premises.
14. WHAT IS A SOUND ARGUMENT?
• An argument must fulfill two requirements in order to be
considered as sound. One requirement is that the argument
must be valid. An argument is valid when its conclusion
follows logically from the premises. In other words, it is
impossible for the premises of an argument to be true while
the conclusion is false. The second requirement is that all its
premises should be true. Thus, a sound argument is a valid
argument that has true premises.
15. THE FOLLOWING IS A SOUND ARGUMENT
AS IT CONTAINS TRUE PREMISES AND IS
VALID.
•Premise 1: All men are mortal.
•Premise 2: Socrates is a man.
•Conclusion: Therefore, Socrates is mortal.
16. WHAT IS AN UNSOUND
ARGUMENT?
•An unsound argument is the opposite of a sound
argument. Thus, an unsound argument can be
either valid or invalid. However, if the argument is
valid, it has at least one false premise in order to
consider it as an unsound argument.
17. WHAT IS AN UNSOUND
ARGUMENT?
•An unsound argument is the opposite of a sound
argument. Thus, an unsound argument can be
either valid or invalid. However, if the argument is
valid, it has at least one false premise in order to
consider it as an unsound argument.
18.
19.
20. LET’S TRY THIS
•Directions: Identify whether the given
statements is a SOUND or UNSOUND
Argument. Be ready to explain your answer.
21. #1
•Premise 1: All cows are mammals.
•Premise 2: All dogs are mammals.
•Conclusion: Therefore, dogs are cows.
22. •Premise 1: All cows are mammals.
•Premise 2: All dogs are mammals.
•Conclusion: Therefore, dogs are cows.
•Explanation: The above argument contains true
premises, but it is invalid since the conclusion
doesn’t logically follow from the premises.
Therefore, it is also an unsound argument.
23. #2
•Premise 1: All cats are pink.
•Premise 2: Toffee is a cat.
•Conclusion: Therefore, Toffee is pink.
24. •Premise 1: All cats are pink.
•Premise 2: Toffee is a cat.
•Conclusion: Therefore, Toffee is pink.
•Explanation: The above is a valid argument too
since the conclusion logically follows from the
premises. However, the first premise is not true.
Therefore, this is an unsound argument.
25. #3
•Premise 1: All tigers are mammals.
•Premise 2: No mammals are creatures with
scales.
•Conclusion: Therefore, no tigers are creatures
with scales.
26. •Premise 1: All tigers are mammals.
•Premise 2: No mammals are creatures with scales.
•Conclusion: Therefore, no tigers are creatures with
scales.
•Explanation: The above is a valid argument since
the conclusion logically follows from the premises.
All premises are true. Therefore, this is a sound
argument.
27. SUMMARY
SOUND VS UNSOUND
ARGUMENT
• Validity and the truth of the premises are the two factors that
determine the soundness of an argument. A sound argument
is an argument that is valid and has true premises while an
unsound argument is an argument that is invalid or has at
least one false premises. Thus, this is the key difference
between sound and unsound argument.
