Hello again. Here's another essay I did in first year, this one's more to do with logic in philosophy. Have a gander and see if it's any good to someone.
Today, the word argument is often misused to mean a heated debate between two people, involving shouting, raised voices, fist waving and other such aggressive behaviour. However, the correct meaning of the word argument is much simpler. An argument is a construction of statements from which a conclusion is drawn. For an argument to “make sense”, so to speak, it must contain a level or validity and/or truth. In this essay I will explain the relationship between the two states.
First of all, I will attempt to distinguish the difference between the terms “truth” and “validity”. Validity is a property of argument whereas truth is a property of assertions. Validity has to do with whether a conclusion follows from an argument’s premises. As we will see later, it is possible to have a valid argument with false premises. That is because the validity of an argument is not dependant on having true premises. The argument is valid only if the conclusion follows logically from the premises. Therefore, when empirical facts are used in the reasoning process, what we concern is the truth of the statements; however when the conditional facts are used, what we concern is the validity of the conditional statements.
In order for someone to construct an argument, it must contain at least one premise. For example, one can state that “all third level students drink Guinness”. From this, the conclusion “some third level students drink Guinness” can be drawn. This argument can be considered a logically valid argument because of the distribution of the subject “third level students” as “some” is included in “all”. Note that whether or not the statement “all third level students drink Guinness” is true or not bears no relevance to the argument’s validity. If the statement or premise is something obviously false such as “all dogs are cats” and the conclusion drawn from this is “some dogs are cats”, this still constructs a logically valid argument.
An argument can have more than one premise. An argument that contains true premises must also have a true conclusion. An argument cannot be valid if it has true premises and a false conclusion. Take the following syllogistic argument for example:
“All third level students drink Guinness.
John is a third level student.
Therefore, John drinks Guinness.”
With the same logic used in the previous paragraph, we can see that the argument is a valid one due to the distribution. In the above argument “All third level students drink Guinness.” is the first premise, “John is a third level student.” is the second premise and “Therefore, John drinks Guinness” is the conclusion. Even though this argument is logically valid, it once again bears no relevance to the truth of the argument. The above argument could possibly be true, i.e. it is not beyond impossibility. The subject of the argument, “third level students”, is the middle term. This term is irrelevant to the truth of the conclusion as no matter what subject is used as the middle term, it does not change the conclusion or it’s truth in any way.
To simplify the inspection of an argument’s validity and truth to convert it to standard logical form. A simple example is to apply the letters “P”, “Q” and “R” to terms “third level students”, “John” and to the set of Guinness drinkers in the above example respectively. Using these symbols, the standard logical form of the above argument can be abbreviated as follows:
“All P is R.
Q is a P.
Therefore, Q is R.”
Using these symbols, the plain logical form of the argument is made clear. Notice now that any argument in the above configuration can be expressed in standard logical form to aid in assessing it’s truth and validity.
While the truth of propositions and the validity of reasoning are distinct, the relationship between the two is not entirely straightforward. We cannot say that truth and validity and totally independent because of the impossibility of a valid argument with true premises and a false conclusion shows that one combination of truth-values is an absolute bar to validity. When an argument has a true premise and false conclusion, it must be valid. This is, in fact, the very definition of invalidity.
One should never be brought by true conclusions or true premises to the assumption that the argument is valid. Nor should valid reasoning lead one to the assumption that the statements are true or by invalid reasoning to suppose that the statements are false.
When truth and validity are combined, this brings about the concept of soundness. An argument is sound if (and only if) all it’s premises are true and its reasoning is valid. All other forms of argument are unsound. It also follows that all sound arguments have true conclusions.
In the example I used above, we saw that the argument is valid but not necessarily true. If we knew (empirically or otherwise) for a fact that all third level students drink Guinness and that John is a third level student, then the conclusion that John drinks Guinness is not only valid but true. This would be an example of a sound argument.
In logic, an argument isn’t so much tested for validity as it is for invalidity. In this essay, I have shown what invalidity in an argument is to have true premises and a false conclusion. An argument that is simply not invalid is technically valid but in a weak sense. But to test for invalidity, one must identify when they are dealing with a true premise and a false conclusion. However, a logician cannot know whether or not a statement is true or false as they deal only in the logic of the argument and not the factual content of the information.
The word argument is indeed often misused today to refer to a heated debate etc. but it is also used correctly as well. In a political debate, two politicians can argue their views to each other or to an audience of people without a single raised word being used. The politicians would state what they believe or what they stand for and give reasons for such, resulting in an argument similar to the ones described above. Their opponent will then try to deconstruct the argument by testing for invalidity by attacking the truth of the statements. Therefore, when one puts forward a valid argument for something, one must also note that the truth of the conclusion is not so disconnected from the validity of the premises as one may have first thought.
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