What are Gettier problems?

A Gettier problem (named after Edmund Gettier) is a reaction to a specific way of thinking about knowledge. So in order to understand what Gettier problems are concerned with, we must first consider the theory which Gettier problems react to. People know a lot of stuff. I know stuff. You know stuff. But what really is this thing we call Knowledge? Epistemology is the branch of philosophy that primarily concern themselves with these kinds of questions. A reductive account may be needed in order to answer the question ‘what is knowledge?’. The aim here is to analyse and describe our concept of knowledge and identify its fundamental components. A popular way of going about this is to think of knowledge as a Justified-True-Belief. This is known as the JTB analysis of knowledge. According to this theory, the conditions you need to satisfy in order to have knowledge is that: 1. you have a belief 2. you are justified in holding this belief. 3. your belief is true. For example: (A) Descartes knows that he exists. For Descartes to have knowledge of A he needs to satisfy the conditions mentioned above. Firstly, Descartes must believe that he exists. Secondly, Descartes must be justified in holding this belief. That is, he must give reasons for holding this belief. (Conveniently enough he does; he famously argues that “I think therefore I am”.) Thirdly, for for Descartes to know A, A must be true. That is, A must be a matter of fact. This means that Descartes needs to exist in order for him to be able to form beliefs about his existence (which he did). Having satisfied all these conditions Descartes can be confident that he knows proposition A, according to the JTB analysis of knowledge. In fact, the JTB analysis of knowledge seems like a pretty convenient, commonsensical account of knowledge. Edmund Gettier, then comes along and offers a counter example to this way of thinking about knowledge. Consider the following scenario: Julie looks at her watch at midday. She forms the belief that it is 12 o’clock. Her belief is justified, perhaps because her watch has proven reliable in the past. Also, her belief is true, because it is in fact 12 o’clock. Unbeknown to Julie, the battery in her watch is malfunctioning. In fact, her watch stopped ticking 12 hours ago. Her justified true belief that it is 12 o’clock is just a matter of luck. We are left with the question of whether Julie can be said to know that it is noon. Every broken watch will tell the correct time twice a day. But as Gettier points out, it is implausible that we can say that Julie really knows what time it is. According to the JTB analysis of knowledge, she has knowledge about what time it is, but this knowledge is merely accidental. We call this epistemic luck. Gettier’s argument takes the form of a reductio ad absurdum. He assumes the position of his opponents (JTB) and shows that from their premises, one can draw absurd conclusions. If we accept the JTB account of knowledge, then we must also accept that much of what we know is attributed to happy accidents. Intuitively we associate knowledge with truth and fact – not matters of luck. Thus, the JTB analysis of knowledge allows us to claim that we know more than we really do. This is problematic. Gettier cases, like the one explained above, therefore provide good evidence for the claim that we cannot define knowledge as Justified True Belief.