Life’s Ultimate Questions
“The Law of
Noncontradiction”
Christopher Ullman, Instructor
Christian Life College
1
Passages that are Nonarguments
Any passage lacking a claim that something is
being proven is a NON-ARGUMENT.
ARGUMENTS contain INFERRED
CLAIMS.
NON-ARGUMENTS contain only FACTUAL
CLAIMS, if that.
Examples:
o The dog is a brown terrier with black paws.
She also has a pleasant temperament.
o I want a glass of water, right now. Give me
yours.
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Let’s Have an Argument!
o We will need three things
1. At least one PREMISE
A.
a statement that is offered as evidence or
as a reason to believe for another statement
is a premise
B. the BECAUSE part of the argument
C. Example
o “Socrates is a man.
o All men are mortal.
o Therefore, Socrates is mortal.”
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Let’s Have an Argument!
(continued)
2. A CONCLUSION
A. a statement in an argument that the
premises are claiming to prove
B. the THEREFORE part of the argument
C. There is only one conclusion per argument
D. Example
o “Socrates is a man.
o All men are mortal.
o Therefore, Socrates is mortal.”
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Let’s Have an Argument!
(concluded)
Where’s the third thing?
3. An INFERENCE
A. The invisible part of the argument
B. The claim that the premise(s) support the conclusion
C. Can be explicit (“Therefore, . . . “)
D. Can be implicit (“A fetus is a person from
conception. Elective abortions are immoral.”)
E. Involves pressure to agree
o
o
It would be irrational to disagree
Good arguments leave the hearer no choice but to agree
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Examples of arguments
o “The price of a gallon of gasoline has been
going up lately. Therefore, it will probably
cost me more to fill my tank next time I need
to.”
o “Jake is an unmarried male. All unmarried
males are bachelors. Therefore, Jake is a
bachelor.”
o “If I can afford to go to Hawaii, I will ask off
for vacation. I just found out the rent check
bounced! And the cat is pregnant . . . again!
Therefore, no surfing for me.”
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Why an Argument Works
o It would be IMPOSSIBLE for the
conclusion of a valid DEDUCTIVE
argument to be false.
o It would be HIGHLY IMPROBABLE for
the conclusion of a strong INDUCTIVE
argument to be false.
o Why?
o Because in both cases, the OPPOSITE
of the conclusion would be a
CONTRADICTION
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The Principle of
Noncontradiction
1.
Its father is the Principle of Identity
o
o
2.
Brother to the Principle of the Excluded Middle
o
o
3.
“It is what it is”
“A = A”
“It either is or it isn’t”
“This is either A or non-A, one or the other.”
Simply stated, the Principle of Noncontradiction
declares contradiction to be nonsensical
o
o
o
“It is not what it isn’t.”
“A  non-A”
A thing (object, person, idea, entity, concept) cannot be
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itself and opposite.
Qualifying the Principle of
Noncontradiction
The thing in question cannot be vague or
ambiguous
o
o
If it is vague or ambiguous, then the principle can’t
be enforced
Your truth claim will get the response, “Well, it all
depends on what you mean by A.”
We must qualify the Principle of Noncontradiction
thus
o
A thing (object, person, idea, entity, concept) cannot
be itself and its opposite at the same time in the
same sense.
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The Necessity of the Principle of
Noncontradiction
The medieval philosopher Avicenna once
said,
“Anyone who denies the law of noncontradiction should be beaten and
burned, until he admits that being beaten
is not the same as not being beaten, and
being burned is not the same as not being
burned.”
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The Necessity of the Principle of
Noncontradiction
It can’t be proven, since it must be true for
any proof to have any worth whatsoever.
However, the following statements provide
indirect and persuasive proof of its
necessity
If the principle is denied, then . . .
A. . . . significant thinking is impossible.
B. . . . significant human conduct is impossible.
C. . . . significant communication is impossible.
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The Best Support for the
Principle of Noncontradiction
o Titus 1:2
o Hebrews 6:18
o Numbers 23:19
o 2 Samuel 7:28
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Today’s Attack on the
Principle
o “The truth is: There is no truth.” – Richard
Rorty
o “Nothing is certain.”
o “Nobody knows anything for sure.”
o “Everything ought to be doubted.”
o “What is true for you may not be true for
me.”
o “If you think it is, then it is. If you think it
isn’t, then it isn’t. It’s all in a person’s mind.”
o “Perception is reality.”
13
Self-Referential Incoherence
When a statement’s truth is applied to the
statement itself, and
 The statement cannot then be understood
to be true, then
 This is an example of self-referential
incoherence
 The conclusion is that the statement
cannot be true without being false

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Examples of Self-Referential
Incoherence
o “The truth is: There is no truth.” – Richard
Rorty
o “Nothing is certain.”
o “Nobody knows anything for sure.”
o “Everything ought to be doubted.”
o “What is true for you may not be true for
me.”
o “If you think it is, then it is. If you think it
isn’t, then it isn’t. It’s all in a person’s mind.”
o “Perception is reality.”
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Postmodernism
1. Pomo is ripened Existentialism, which
taught that . . .
A.
B.
C.
D.
. . . Chance replaces Destiny
. . . Freedom replaces Rules
. . . Experience replaces Reason
. . . “Life’s a bad joke. You have to
make the best of it, by making choices,
and sticking to them.”
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Postmodernism teaches there
can be no . . .
2. . . . Underlying meaning
3. . . . Absolutes
4. . . . Objective morality
5. . . . Objective basis for values
6. . . . Individual selves
Why?
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“ . . . Because Truth is
Constructed”
o All beliefs are formed in the context of
a society of one kind or another
o It’s impossible to escape the influence
of that society
o Societies create “truths” so that power
can be obtained and securely held
o Every “truth claim” has an ulterior
motive, so . . .
o Be suspicious. Be very suspicious!
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The Vaccination for
Postmodernism is
The Principle of Noncontradiction!
19
Some Truths About Truth
1. A statement is true if it corresponds
to reality
2. A statement is false if it does not
correspond to reality.
3. All truth claims are absolute, narrow
and exclusive.
4. Truth is discovered, not invented.
o
It exists independently of anyone’s
knowledge of it.
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Some Truths About Truth
(continued)
5.
Truth is indispensable for living.
o
Consider the need for truth in matters relating to
A.
B.
C.
D.
E.
6.
7.
8.
Safety
Money
Relationships
Transportation
Court proceedings
Beliefs cannot change a fact.
Truth is transcultural.
Being raised in a given culture doesn’t
make the beliefs of that culture true.
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Some Truths About Truth
(concluded)
9. Truth is not affected by the attitude of
the one professing it.
10. Contrary beliefs are possible, but
contrary truths are not possible.
11. We can believe everything is true, but
we cannot make everything true.
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. . . but none of this is true, if the
Principle of Noncontradiction is
ignored!
23
Some Truths About Logic
1.
2.
3.
4.
o
5.
Logic makes it possible to compare truth
claims.
Truth claims about God require logic to be
supported.
This means our knowledge of logic is prior to
our knowledge of God.
In one sense, God is not subject to logic.
Our statements about God ARE subject to
logic.
In another sense, God is subject to logic, since
logic represents the principles of rational
thought, and God is a rational being.
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. . . but none of this is true, if the
Principle of Noncontradiction is
ignored!
25
Do we want to live in a world
where Truth and Logic are thought
to be Impossible?
If so,
WELCOME TO THE JUNGLE!
YOUR AVAILABLE OPTIONS:
 Rage
 Roar
 Run
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Escape from the Jungle
is Possible

John 114


John 146


Jesus answered, "I am the way and the truth and the life. No one comes
to the Father except through me.”
John 1717


The Word became flesh and made his dwelling among us. We have
seen his glory, the glory of the One and Only, who came from the
Father, full of grace and truth.
“Sanctify them by the truth; your word is truth.”
John 832

“Then you will know the truth, and the truth will set you free.”
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Escape from the Jungle
is Possible
if and only if the Principle
of Noncontradiction is not
ignored
...
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