Please read the disclaimer at the top of the atheism page before proceeding, thank you. Also some good sources of learning on the subject are listed at the bottom of the page.
Epistemology is the study of knowledge and justified belief (1). There are a lot of related questions such as what justifies justified knowledge and beliefs? What conditions does knowledge need to meet to be considered knowledge? And so on.
Knowledge requires three things to exist:
- A True Proposition: An expression in language or signs of something that can be believed, doubted, or denied or is either true or false(2). The proposition must be true for false propositions cannot be known.
- Belief: Knowledge requires a belief for a proposition that someone does not believe can not be a proposition that a person knows.
- Justification: To eliminate the possibility of luck the knowledge must somehow be justified.
Once all of these conditions are met you have what’s called a tripartite or a justified true belief (JTB).
The Gettier problem
The Gettier problem is concerned with condition number three: justification. It seems logical to ask, what is considered justification? The Gettier problem has been explored at great lengths and two good online explorations can be found here and here.
What is Justification?
There are two kinds: internal and external. Internal deals with perception, introspection, memory, and rational intuition. Internalists say that these cognitive processes are reliable and so count as justification. Externalists argue that none of these are reliable enough to considered justification. There are, however, five commonly accepted sources of knowledge and/or justification:
- Perception: This involves our senses and has two schools of thought: direct and indirect realism. Direct realism says we can acquire knowledge because we can directly perceive things. Indirect realism says you don’t perceive something but rather the sensory data (or something similar) of the thing being perceived. Of course using perception as a means of justification and/or knowledge begs the question ‘are our sensory perceptions reliable?’ There is no way out of circular arguments about the reliability of sensory perception and so is therefore not typically considered a reliable source of true knowledge.
- Introspection: Introspection is a reliable way of understanding one’s state of mind but nothing else. Introspection can be unreliable in specific cases (i.e. mistaking an itch for a minor pain) but is almost entirely an infallible source of information of on our own state of mind.
- Memory: Memory is a problematic and unreliable source of knowledge and/or justification. It is because of this that in philosophical circles there are two types of memories: remembering (which entails truth) and seeming to remember.
- Reason: A reliable source of true knowledge and/or justification because it is a priori (prior to any kind of experience). A person is justified in believing a proposition if and only if their justification for believing that proposition does not depend on any experience. Experience being anything perceptual, introspective and memorial. An entire page will be dedicated to logic and a reason because understanding and knowing how to use it is very important in having a solid understanding of anything.
- Testimony: Testimonial knowledge/justification is only as reliable as the source and so is not used as a source of information in scientific and logical matters.
Please read through the following sources to explore Epistemology further as many more issues and discussions remain such the limits of knowledge and justification and subtypes of Epistemology such as religious or feminist.
- Epistemology: The Theory of Knowledge (Philosophy in Focus) By Daniel Cardinal
- An Inquiry Concerning Human Understanding by David Hume