Theory of Knowledge
In the dialogue of Thaeteus written by Plato, Thaeteus argues that Knowledge = Justified True Belief. It is almost universally accepted that K=JTB is the best definition of knowledge, however this theory does not exist without its detractors. We can never say that Knowledge is Justified True Belief due to various issues that arise when this theory is put forward. Therefore the theories on how Knowledge = Justified True Belief will be explained and compared in an attempt to show why we can never say ???I know that P??™.
Belief is considered a key factor in the traditional description of knowledge. A belief is something that exists without sufficient proof or facts. We must believe something for it to become knowledge. So a belief can be false or true, but it must be true to become knowledge. Knowledge is assumed to be infallible as justification implies that it cannot be wrong, yet many epistemologists have argued that the infallibility of knowledge is arguable. We can say that a proposition is justified on the foundation of facts, yet the problem of induction shows that knowledge can be fallible as perception is used to validate this. This raises the point of the infinite regress of reasons where one proposition has to be justified by another. Therefore if we factor in the theory of infinite regress, our propositions will eventually become self-referring or lead us to a contradiction without justifying the proposition. Foundationalism attempts to defeat the argument of infinite regress by saying that there are some beliefs where it is unsuitable to ask for justification which are called ???basic beliefs??™. So the idea of basic beliefs allows us to say that the chain that is the supporting reasons for a belief cannot go back forever, rather it is terminated.
Descartes said that we are all born with innate ideas ???We come to know them by the power of our own native intelligence, without any sensory experience. Hence, according to Plato, Socrates asks a slave boy about the elements of geometry and thereby makes the boy able to dig out certain truths from his own mind which he had not previously recognized was there, thus attempting to establish the doctrine of reminiscence.??? (1643 letter, Oeuvres de Descartes, 8b:166-67).
Descartes believed we could obtain basic beliefs through our intuition which are self-evident and indubitable, while Empiricists expanded on this by adding that perception could be used to add to what defines basic beliefs. Synthetic propositions and analytical propositions are both possibilities for basic beliefs. An analytic proposition contains a judgement of subject-predicate form. An example would be ???All bachelors are unmarried???. The concept of unmarried also comes under the concept and definition of a bachelor. Descartes argues that any analytic proposition that is true is knowledge under the theory that knowledge is justified true belief. The theory also contradicts the conditions that define knowledge. Therefore due to the ability to make it possible for future change, Critical Rationalists look upon Synthetic Propositions as being a solid basis on which to define knowledge. Locke developed the ???Tabula rasa??? where Locke says that we are born without innate knowledge or rather we are born with a blank slate and learn from our experiences. Yet, this theory is dependant on using our senses which have been proven as fallible. It is also suffers from the Infinite Regress of Reason theory and the issue of induction which are the main problems linked to Knowledge.
Critical Rationalists define knowledge through trial and error. (Popper, Open Society and it??™s Enemies, 1984, P. 46). Our experiences teach us and we learn from our errors. Science can show us what is unlikely, but they cannot show us what is impossible. It is also said that for a theory to be considered scientific, it must be shown to be falsifiable also. So while the theory may be shown to be incorrect, it does not mean that the theory does not have any truth to it. If we were to say that all ???swans are white??™, until it is proven wrong, then we can justify this as knowledge. However, if I find a black swan then the theory that ???all swans are white??™ is forgotten and a new theory is developed, one that states all swans are either black or white. We can often misevaluate the strength of our evidence. If it stronger or weaker in the search for true belief, we can be led to adopt or retain false belief.
We use the theory of Knowledge is Justified True Belief in an attempt to define Knowledge and make it a definite concept. However, when we use this theory, a number of problems arise. If we attempt to make knowledge a definite concept, then knowledge becomes useless. Therefore to say ???I know that P??? would be incorrect and hence should never be said.
Stephen Thornton, First published Thu Nov 13, 1997; substantive revision Mon Feb 9, 2009
John Vickers, First published Wed Nov 15, 2006; substantive revision Mon Jun 21, 2010
William Uzgalis, First published Sun Sep 2, 2001; substantive revision Sat May 5, 2007
Eric Schwitzgebel, First published Mon Aug 14, 2006; substantive revision Sun Nov 21, 2010