Another post I wrote a few years ago for a theory of knowledge course.
One of the questions considered in all ages is: What is truth? There are many opinions on this and I investigated Platos’ definition of truth. I also looked at three modern theories approach to a definition of truth; the pragmatic theory of truth, the correspondence theory of truth and the coherence theory of truth. I also looked at what they considered factors of truth and why those factors where important for truth.
For a statement to be true according to Plato the statement had to pass three tests. The first test is believing the statement, second test is that it must be true (determined by if it is public, eternal and independent) and thirdly the statement must be justified (by logic, memory, authority or by empirical evidence). The reason why Plato considered that one has to believe the statement for it to be true is that if one does not believe a statement one can not “know” that it is true. Plato only considers public truths to be true; only universal laws are true. The statement must be eternal, the public can not change their opinions about how it was before. (e.g. if a ball was red, it will always be red at that particular time).
The pragmatic theory of truth can be defined as: “Concepts or propositions that are proved to be worthwhile or useful are true. This we only know through our subjective experience”. Basically it is a subjective theory that looks at what you think and what you think is useful. This theory does not establish any universal laws, only personal truths which might at some instances cohere with what other people think is true. Without belief in the statement it will never be true.
The Coherence theory can be defined as: “Concepts or propositions are true if they cohere with already established truths, which are accepted as truths, that is, they coheres with them”. A logical argument for truth that has a big problem since it is building on accepted truths. Then one has to ask oneself what an accepted truth is. According to this theory it is something that builds on another accepted truth which builds on another accepted truth and etc. It all comes down to that everything is based on an assumption from the beginning and hence nothing is true. The best example of this theory is shown in math where everything is based on the assumption that 1+1=2. If one accepts that everything is built on an assumption, there is still a big difference amongst people what they consider to be an accepted truth.
The correspondence theory of truth may be defined as: “Truths occurs when the concept or proposition corresponds to the objective reality which it describes”. Basically this is an experience theory, one needs to experience the statement one has made to be able to establish that it is true. This theory makes it hard to establish truths since one has to experience the situation during which they occur.
By trying the truth of a statement according to the four different theories one can see how the theories work and the weaknesses with them. The statement that I will test is: The president of United States is a bad president. According to Plato for it to be true it has to be believed. It has to be true, which means that it has to be public, independent and eternal. The statement is not independent since the president treats people differently hence a person from Iraq has a different view on it then someone from another country. It may be eternal but that depends on what you determine as to be good in the future. Today it might be good that the president fights terrorism on a big scale but in the future they might think it is bad since it creates more terrorists and more threats then there was a need for. The justification can always be argued to either side. One can support it by some other president saying that he is a good one (authority) or through memory remembering something good he has done. If one looks at the pragmatic theory it totally depends on who utters the statement if it is true or not to that person since there is no universal law and people think differently. According to the coherence theory it coheres with the facts that fighting terrorism is good but it also coheres with the fact that wars are bad. Thus contradicting and creating no answer. The correspondence theory says that you have to experience it hence one has to be maltreated or see someone be maltreated by him to say that the statement is true.
My conclusion is that the coherence theory is very hard to use since it often contradicts itself and also have a problem of creating an universal law since there are different opinions of what an accepted truth is. This theory is built on an assumption which all the accepted truths are built on which makes it into a very weak theory. The pragmatic theory is good since ones mind determines what is true and what is not Even if there is an universal truth it still has to pass the test if you think it is true or not. It is very subjective and can not (often) be used in scenarios where many people are involved in, if a statement is determined to be true or false. As long as the answer only affects you it is a perfect theory. Correspondence theory is vague since it has to be experienced and it takes a lot of time to experience all ones statements Sometimes it is impossible to experience ones statements and thus it can not be determined to be true or false. It is also hard to determine if a statement is false. When one experiences the situation it might be the wrong time and it will happen next time hence one has to experience it again. This theory is commonly used in science. Plato’s theory is the best theory since it has many small tests to determine the truth but it only accepts universal laws and most of the statements are subjective hence most of the statement are not true. Plato says that the statement has to be true for everyone but he also says that it must be authorized and people look differently on the authorization.
[pic: CC-BY-ND, h.koppdelaney]