Sources and Types of Knowledge – CUET PG Philosophy – Notes

Sources of Knowledge

Epistemology, or the theory of knowledge, is a fundamental branch of philosophy that investigates the nature, origin, scope, and limits of human knowledge. It grapples with core questions such as: What does it mean to know something? How do we acquire knowledge? How can we be certain of what we know? Central to this inquiry is the identification and analysis of the sources from which we derive knowledge. These sources are the pathways or mechanisms through which we gain justified true beliefs about the world.

The Traditional Analysis of Knowledge: Justified True Belief (JTB)

For centuries, the dominant view in Western philosophy, tracing back to Plato, has been that knowledge can be defined as Justified True Belief. This tripartite analysis breaks down knowledge into three essential components:

• Belief (B): This is the subjective condition. To know a proposition (e.g., “The Earth revolves around the Sun”), one must first believe it. If you do not accept a proposition as true, you cannot be said to know it. Belief is the internal, cognitive state of assent.
• Truth (T): This is the objective condition. The proposition you believe must actually be true. It must correspond to reality. You cannot know that “The Earth is flat” because the proposition is false, even if you fervently believe it and have reasons for that belief. Knowledge must be of what is the case.
• Justification (J): This is the crucial link between belief and truth. Your true belief must be supported by adequate evidence, reasons, or grounds. This condition is necessary to rule out lucky guesses or accidental true beliefs from counting as knowledge. For instance, if you believe a lottery ticket will win based on a random hunch, and it happens to win, you had a true belief, but you did not know it would win because your belief was not properly justified. Justification is what makes a belief epistemically responsible.

The quest for the sources of knowledge is essentially a quest for valid forms of justification. The different sources are the different ways we can justify our true beliefs.

The Gettier Problem: A Challenge to JTB

In 1963, Edmund Gettier published a short but revolutionary paper that challenged the adequacy of the JTB definition. He presented counterexamples, now known as “Gettier cases,” in which a person could have a justified true belief that still does not seem to be knowledge. Typically, these cases involve a justified belief that happens to be true due to a stroke of luck, where the justification is not properly connected to the truth of the belief.

For example: Smith is told by his boss that his colleague Jones will get a promotion, and Smith has also seen that Jones has ten coins in his pocket. Smith thus forms the justified belief: “The person who will get the promotion has ten coins in his pocket.” However, unbeknownst to Smith, it is he, Smith, who will get the promotion, and he also coincidentally has ten coins in his pocket. In this case, Smith’s belief is true, and it is justified (based on what the boss said about Jones), but we intuitively feel that Smith does not know it. His justification points to Jones, but the belief is true because of Smith. This shows that JTB might not be a sufficient condition for knowledge, leading to decades of debate about adding a fourth condition or revising the nature of justification.