"gettier Problem" Study

The tripartite definition of traditional knowledge considers knowledge asjustified true belief. But on the basic of justified true belief, Gettier devised twocounterexamples which are not knowledge. The appearance of Gettier'scounterexamples has a large influence, although it has been challenged, mostphilosophers admit their value, and use different ways to revise the definition ofknowledge.The article first introduces the tripartite definition of traditional knowledge,which is generally accepted by philosophers, but Gettier devised two counterexamplesto prove justified true belief is not surely knowledge. The counterexamples proved thetripartite definition which is not sufficient and necessary condition to knowledge, sohow can we give a definition on knowledge? How can we perfect knowledge? Thoseproblems were considered as "Gettier Problem".Many Gettier-type counterexamples which are similar to Gettier'scounterexamples are devised. This article also introduces some typical Gettier-typecounterexamples, chooses the paradox of surprise examination, compared it withGettier's counterexamples from the aspect of knowing.Gettier-type counterexamples were challenged. Philosophers who challenge it aremainly on the principle of the counterexamples presupposed, although thosechallenges are reasonable in some sense, after carefully analyzing these viewpoints,this paper concludes that they have their own shortcomings. Of course, it dose notmean that Gettier's counterexarnples are perfect, because this article also proves thatthey have some defects.The field of epistemology's mainly trend is towards to how to solve "GettierProblem". On the question of how to define knowledge, some philosophers hold theview that one more condition should been added besides three original conditions,while others approve of using new condition to replace the original condition. Thisarticle introduces causal theory, indefeasibility theory, conditional theory andcontextual theory. This paper also gives a simple comment on these kinds of theories.However, the Gettier Problem is so complicated that no pattern has been universalityaccepted so far.At the last part, the paper analyzes the cause of Gettier Problem. This paper also tries to put forward a new definition for knowledge.