In the Western philosophical tradition, knowledge is defined as justified true belief, which requires that beliefs are not only true but also have sufficient grounds. Gettier argues that these three elements do not adequately describe knowledge, and explores the justification of beliefs through the debate between internalism and externalism.
In the Western philosophical tradition, knowledge is understood as “justified true belief”. The reason why having true beliefs is insufficient to say that we have knowledge is that we may hold true beliefs by accident. For example, if we happen to believe something by accident and it turns out to be true, we don’t have knowledge. This discussion shows that a belief is epistemically justified only if we have good reasons or grounds for thinking it is true.
In traditional epistemology, a proposition P is said to be true if it is in fact true, a cognitive subject S believes it, and S has good reasons or grounds for his belief that P. In other words, we have knowledge if the three elements of justification, truth, and belief are met. This view has long shaped our understanding of knowledge, and philosophers have used it to explore the nature and conditions of knowledge.
It was Gettier who suggested that the three elements of knowledge, widely accepted in traditional Western epistemology, are not necessary and sufficient conditions for knowledge. Through several thought experiments, Gettier argued that these three elements do not adequately explain knowledge. One of his most famous examples illustrates his argument. A cafe is showing a soccer match between South Korea and Japan. I infer that there are a number of Koreans in the café, and the cheering I hear leads me to believe that Korea has just scored a goal, and indeed, Korea has scored a goal and it is now 1-0. At this point, my belief that South Korea just scored a goal is justified and true. However, the cheering I actually heard was coming from the office upstairs in the café, and it was from a promotion celebration that took place just as South Korea scored. Therefore, my justified, true belief is not knowledge. In other words, Gettier’s objection is that there are justified true beliefs that are not knowledge. Epistemologists since Gettier have tried to create a justification criterion to solve this problem. In the process, the question has arisen whether the determinants of justification are intrinsic or extrinsic to the cognitive subject.
The basic position of internalism is that the justification of beliefs lies in the relationship between beliefs. For example, when I believe that the Earth is round, the justification for this belief is my belief in the scientific facts and my belief in the photographs of the Earth from space, which are the reasons for my belief that the Earth is round. Thus, internalism holds that it is the other beliefs of the cognizer that determine the justification of a belief. In order for a belief to be justified, the cognitive subject must be able to think about the justifying factors.
On the other hand, the basic position of externalism is that the justification of beliefs is based on objective grounds, i.e., the objective grounds that have undergone a reliable cognitive process. For example, suppose I am standing in front of a book and I believe the proposition “There is a book in front of me. Externalists believe that my belief is justified by the objective evidence obtained through a credible cognitive process that I am seeing the book in front of me with my own eyes. Some externalists also believe that the justification of beliefs is determined by the causal relationship between facts and beliefs.
In addition to this, the question of the reliability of beliefs is an important issue in epistemological discussions. According to credibility theory, a belief is justified if it was formed by a reliable cognitive process. This is a concept closely related to externalism, which states that the justification of a belief depends on how reliable the process of its formation is. This approach has important implications, especially when it comes to the justification of scientific knowledge. Since scientific methodology relies on reliable procedures and repeatable experiments to form knowledge, reliability theory is an important part of scientific epistemology.
There is still a debate about the correct epistemological perspective, as both internalists and externalists can offer their own conception of knowledge. This debate provides important insights into the nature of knowledge and under what conditions beliefs can be justified. These debates also have implications beyond philosophical inquiry into practical knowledge acquisition and application. For example, how knowledge is transmitted in education, the evaluation of legal evidence, and issues of credibility in everyday decision-making play an important role.
