Definitions of Knowledge
Definitions of Knowledge
In order to answer this question, must assess whether each of the above are necessary to having knowledge, and then consider whether any other requirements must be added.
Traditionally, knowledge is believed to constitute three requirements. They are that the thing which is known must be true, the person who knows it must believe the fact to be true, and he must have justification for his belief. This idea can be shown in the following way. s only knows q if
1. q (meaning that q is true)
2. s believes in q
3. a's belief in q is justified.
This is known as the tripartite definition, due to there being three parts to the definition. Let us consider each aspect and decide on its value in this definition.
The first principle claims that one can only know q if it is true. This seems reasonable. I could not be said to know anything that was false. I cannot know that the Battle of Hastings took place in 1061 if the idea itself is false. Truth is a crucial criterion for knowledge.
The second principle claims that one can only know q if one is in a state of belief concerning it. This also is reasonable. If I do not believe something to be the case, I cannot possibly be in a state of knowledge. If I do not believe that The Battle of Hastings took place in 1066, then I cannot be said to be in a state of knowledge concerning such a fact. If one fails to agree with something, he cannot have knowledge concerning its truth.
The third principle is equally important. If criteria one and two were satisfied, I might still not be said to have knowledge. For example, I might believe that a football match took place yesterday between Ipswich football club and some other team. If this turned out to be true, I would have belief in a truth. However, it was just a fortunate guess, there was no justification for such a belief, and hence it cannot be considered knowledge, because there was no foundation to my belief.
Therefore, the aforementioned principles of belief seem to be essential criteria for having knowledge. However, they are not enough on their own. E.L. Gettier in 1963 composed examples where the above are satisfied and still do not lead to knowledge. For example,...