Law Of Contradiction

by Walter R. Dolen

What is the Law of Contradiction?

There is no greater principle in thinking than the Law of Contradiction, which is also known as the Law of Non-Contradiction or the Principle of Contradiction. What is the Law?:

"Now the best established of all principles may be stated as follows: The same attribute cannot at the same time belong and not belong to the same subject in the same respect ... This I repeat, is the most certain of all principles...." [Aristotle in Metaphysics]

"There is a principle in existing things about which we cannot make a mistake; of which, on the contrary, we must always realize the truth — that the same thing cannot at one and the same time be and not be, nor admit of any other similar pair of opposites...." [Aristotle in Metaphysics]

"The most certain principle of all is that regarding which it is impossible to be mistaken; for such a principle must be both the best known … and non-hypothetical. For a principle which every one must have who understands anything that is, is not a hypothesis; and that which every one must know who knows anything ... Evidently then such a principle is the most certain of all ... It is, that the same attribute cannot at the same time belong and not belong to the same subject and in the same respect." [Aristotle in Metaphysics]

Aristotle is reported to have written this in his Metaphysics. Aristotle further said that "everyone in argument relies upon this ultimate law, on which all others rest." He said this principle or law of logic "must be known if one is to know anything at all." He also said, "if everything is and at the same time is not, all opinions must be true."

If everything is and at the same time is not ...

Aristotle was right. There is no greater principle in thinking than the Law of Contradiction. Something cannot be all black and at the same time be all white. But a wall can be all white at noon time, and be all black at one hour past noon, because it was painted black shortly after noon time. Or for that matter, something cannot appear to be all white to a certain individual, and at the same time appear to the same certain individual as any other color. Either the object at that time was all white or it was not. But for those who ignore the Law, they say without blinking their eyes:

• the wall is all black at the same time it is all white, or the wall is simultaneously all black and all white

You protest. You say, no one would say that a wall can be simultaneously all black and all white? Do read on.

At the same time ...

A man cannot be legally married and not be legally married at the same time. But a man named Joseph can be married at noon time on Tuesday, and not be married at two minutes past noon time because his wife died at one minute past noon. But this Joseph was not: married and not married at the same time. Although you can say that on Tuesday Joseph was single, he was married, and he was widowered; Joseph was not single, married, or widowered at the same time even though on the same day he was all three.

Good and Evil at the same time or ...

A man cannot be good (in the truest sense of the word) and yet at the same time commit murder. But John could have killed Joseph last year, yet today be good because he has changed from his former behavior. He is a reformed murderer. In the English language, you can still call this John a killer because in the past he killed Joseph, and you at the same time could call John, "good," because he has reformed. But you cannot say that John was good when he murdered Joseph. Time has an important part to play in the Law of Contradiction. Your general behavior cannot be good and evil at the same time, but your general behavior could have been bad in the past, and yet you have now changed your general behavior to that which may be called good.

An Example of Paradoxes and Time

In testimony at a trial, three witnesses testified that they saw illegal drugs being sold from a certain house on a certain day. (All houses on the block looked the same, had no street numbers, but did have different colored garage doors.) Each witness described the house, but each witness described the color of the garage door at the house as being a different color. One said it was brown, one said it was red, and one said it was green. This contradiction almost led to the home owners (husband and wife) being freed, except for the last witness. The last witness, who lived across the street from the house in question, explained that the normal color of the garage door was brown, but at 11 am on the day in question the owner came out and sprayed it red. His wife came home from shopping that same day at 12 pm and the witness could hear the man and woman arguing. She apparently didn’t like the color. So the husband at 1 pm that same day came out of the house and sprayed the garage door green. On the same day the color of the garage door was brown, red, and green, but never was the garage door all three colors at the same time.

What at first appeared to be a real contradiction, later just turned out to be explainable. Time played an important part in this story. At one time the garage door was brown. Later it became red. Still later it became green. The garage door was not brown, red, and green at the same time even though on the same day the door was all three colors. On this same day, in time, the door became different colors. Time played a significant role in this story, as does time play an important role in the understanding of the apparent paradoxes pertaining to God.

Same time in the same respect

Because of the Law of Contradiction, you cannot be physically present on First Street in San Jose, California at 1:30 PM on April 20 and at the same time be physically present on First Street in New York, New York. Of course those who play word games could say that at the same time you were mentally in San Jose, you were physically in New York. Notice the change in the sense of being in a place. For those who play word games, Aristotle qualified his statement: "the same attribute cannot at the same time belong and not belong to the same subject in the same respect." His qualification, "in the same respect," means that you cannot be, in the same sense, in San Jose and New York at the same time.

"If everything is and at the same time is not, all opinions must be true"

If the Law of Contradiction is not correct, you could say that John murdered Joseph at 1:30 PM, or just as truthfully say that the same John did not murder the same Joseph at 1:30 PM on the same day. Both of these contrary statements can be truthful at the same time, if the Law of Contradiction is not true. Again, if the Law of Contradiction is not valid, you could say and be ‘correct’: "I am alive physically, yet in the same sense and at the same time that I am alive — I am also dead." But you protest again. No one you say in their right mind would say he is alive and dead at the same time in the same respect. But –

Word Games or Lies

The Law of Contradiction is so obviously valid that few say it isn’t true, yet there are many who act as if the Law of Contradiction is not true by their belief in contrary theories. In fact, impossible contradictions are taught as truth each day in the fields of religion, politics, law, and "science." If contradictions are taught by "respected" people, they are accepted by some, even though at some level of thought they see the contradiction. Authority and tradition are strong — so strong that real contradictions are taught as the absolute truth. Many dogmas use obviously false statements such as claiming:

"The simultaneity of Jesus’s death and immortality" (Hugh Ross, Beyond the Cosmos, p. 108).

How can Jesus be immortal and simultaneously experience death? There is a way to move beyond the paradox of Jesus being God, yet Jesus dying, without tossing out the Law of Contradiction. In order to know anything we must hold on to the Law of Contradiction. The theologians are making a mistake in their beliefs that force them to ignore and degrade the Law of Contradiction. You cannot find the Truth without using the Law of Contradiction.

Do words have meaning?

Look again at the statement from the astronomer Hugh Ross, a person with a Ph.D in a astronomy:

"The simultaneity of Jesus’s death and immortality" (Hugh Ross, Beyond the Cosmos, p. 108).

Ross is not simple. But because Ross and others believe that Jesus is God, and that God is not mutable or changeable, then in order for Jesus to die on the cross, he must have been dead and alive at the same time. Instead of examining their immutable theory they insist on saying that God was alive and dead at the same time.

Do words have meaning? Apparently not for some theologians. Berkhof wrote:

"In view of all this [scripture] it may be said that, according to Scripture, physical death is a termination of physical life by the separation of body and soul. It is never an annihilation... Death is not a cessation of existence, but a severance of the natural relations of life. Life and death are not opposed to each other as existence and non-existence, but are opposites only as different modes of existence. It is quite impossible to say exactly what death is. We speak of it as the cessation of physical life, but then the question immediately arises, Just what is life? And we have no answer." [Berkhof, Systematic Theology, p. 668].

I do not believe that Berkhof does not understand what death is. He merely doesn’t want to believe it because of some view he holds. In order for some to believe in certain theories they must either change the normal meaning of words (death is not death) or diffuse its meaning. How can death be a different mode of existence as Berkhof maintains? He completely negates the meaning of death by asserting this. This is a ploy used by those who do not wish to look the truth in the eye. When their theory on the nature of God cannot hold up, they merely change the meaning of words, or make preposterous statements that claim and maintain:

"The simultaneity of Jesus’s death and immortality" (Hugh Ross, Beyond the Cosmos, p. 108).

True knowledge cannot exist outside the Law of Contradiction

The Law of Contradiction is true. Once explained and understood it is the most obvious law. It is the basis on which we judge what is true and what is not true. It is the basis on which courts judge whether a person committed a crime or not. Either the murderer was at the crime scene at the same time as the crime or he was not. He could not, be there and not be there, at the same time in the same respect.

Summarize the Law of Contradiction

The Law of Contradiction is the basis from which we reason:

• something or some specific action cannot at the same time be and not be in the same respect/sense.

But there are some, as Aristotle noted, that foolishly argue against this law. But I ask, how can anyone not believe in this law? If someone does not believe in this law, he cannot prove or disprove anything (at any one time something could be or could not be true); he cannot believe in anything (for what he believes in could just as well not be true).

One Argument Against the Law

River. Plato in his Cratylus wrote:

Heraclitus, I believe, says that all things pass and nothing stays, and comparing existing things to the flow of a river, he says you could not step twice into the same river. (Plato Cratylus 402a)

This is a statement from Plato; we don't have the full statement in context from Heraclitus' own writings. We do have this from other alleged river fragments:

Into the same rivers we step and do not step, we are and are not. (Heraclitus Homericus)

It is not possible to step twice into the same river according to Heraclitus, or to come into contact twice with a mortal being in the same state. (Plutarch)

According to the Law of Contradiction a river cannot be a river and not be a river at the same time in the same respect. But according to the river argument of Heraclitus and his followers, a river is never the same from second to second since it is always changing.

"What did Heraclitus mean? The river is always changing. The water into which you put your foot the first time is no longer there the second time you dip your toes into the flow." [God Problem, by Howard Bloom)

To the Heraclitusians way of thinking this disproves the Law of Contradiction. But does it?

Yes it is true that everything is changing in some sense. Yes, the water in the river is moving continuously, since if it didn't, we would not call it a river, but a lake. Most people understand this. Notice Bloom says the same "water" is no longer there. He changes the subject from river to water to make his point. Bloom uses a sleight of hand. He changes the sense of the statement by using "water" to make his argument instead of river. The word river means a body of water moving and changing as it moves. The only way a river can stop being a river is for the water to stop flowing. We call a body of water a river precisely because it is a flowing body of water, not a stagnated body of water.

Philosophers call Heraclitus' continuous changing idea, his flux doctrine. It is a special case of the unity of opposites, pointing to the way things are both the same and not the same over time (first time v. second time you put your foot in the river). Notice that the Law of Contradiction states that something cannot be and not be at the same time. The Law is not speaking about a period of time, but a point in time. And notice that the Law talks about the thing or action cannot be and not be in the same respect, which means you must make your argument against the Law by referring to the same thing in the same respect. By changing the argument from river to water (or to the atoms in the water as others do) you are not talking about the same thing, you have changed the subject, you have used a sleight of hand. It is either a river or not a river. It can never be a river and not a river at the same time in the same respect.

Aristotle sums this up in his Metaphysics (XI. v. 8):

"Perhaps even Heraclitus himself, if he had been questioned on these lines"

["he who says that A is and is not denies what he asserts, and therefore denies that the term signifies what it does signify" (Metaphysics, XI. v. 5) -- he denies the meaning of "river"]

"would have been compelled to admit that opposite statements can never be true of the same subjects; as it is, he adopted this theory through ignorance of what his doctrine implied."

A full understanding as to what Aristotle said makes an argument against the Law futile.

Buy the author's books here

[Copyright (c) 1989-2013 by Walter R. Dolen]