In this post, we’ll talk about one of the most popular contemporary definition of knowledge, the Justified True Belief theory and the conditions it relies on.

The contemporary consensus: Justified True Belief

Pick up an epistemology textbook and the first thing you’ll likely find is what is known as the standard analysis. The standard analysis provides as close to an “official” definition of knowledge as philosophy has ever given, but it’s important to note that the standard analysis is not a universal consensus and has lost some support over time. Still, it provides a working definition that can be used as a foundation for analyzing some contemporary issues in epistemology.

The standard analysis can be broken into three components. Something counts as knowledge if it is: 1. justified 2. true 3. a belief. This is often expressed simply as Justified True Belief (JTB theory). It’s important to know that the knowledge affirmed by JTB is with relation to declarative knowledge, and each of JTB’s components can be broken down and analyzed for clarification.

What does “justified belief” mean?

Simply put, some conceptions of knowledge like the justified true belief theory rely on justification or the reasons by which specific beliefs are favored over others. Below is a list of theories regarding the nature of justification. These theories address issues like where justification comes from or how justification is structured. Additionally, some of these theories can be applied to the nature of knowledge itself:

Theories dealing with the source of justification/knowledge

Internalism. One of the more popular theories around what can count as a source of justification, internalism articulates that everything needed to justify a belief is accessible to a person inside of their head. This can include content like mental states or sensory inputs which individuals experience directly. It can be argued that internalists are people who think “good reasons” are at the heart of justification; if one can’t reason or reflect to access justifications there is essentially no reason to believe something. When Descartes embraced radical skepticism and tried to reason his way back to an understanding of the world, he was essentially embracing internalism. As a result of Descartes’ influence, internalism became popular and remained so for some time after his death.

Externalism. This theory is the rival to internalism, and one of the biggest debates in contemporary epistemology is the Internal-External (IE) debate. Externalism suggests that conditions outside a person’s mind need to be met before that person is justified in believing something. Conditions can be many things, such as beliefs being justified by processes or sources in the world that are themselves reliable. Externalism doesn’t necessarily exclude internalism entirely, but for an externalist, internal beliefs are neither necessary nor sufficient of themselves for justification. Conversely, however, internalists only accept internal justifications.

Theories dealing with the certainty surrounding justification/knowledge

Fallibilism. Fallibilism is the pragmatic suggestion that all of our best beliefs are only fallibly justified. Given the limitations of our cognition, as well as the limitations of our senses, there’s room for reasonable doubt regarding the outright validity of many of the justifications we provide for our beliefs. This doesn’t make our beliefs wrong, nor does it mean true knowledge is impossible to obtain, it just means that there will never be absolute certainty regarding the exact nature of our justifications in relation to the knowledge they provide.

Skepticism. While fallibilism allows for our justifications to have some degree of validity, if only tentatively, skepticism fully denies our justifications any validity. In short, nothing can be proven at all. There are different degrees of skepticism, and while the line between fallibilism and skepticism can be murky, nearly all forms of skepticism have a far more critical stance regarding the nature of justification and belief. Skepticism enjoys some proponents, but many philosophers have used the idea of skepticism – usually towards knowledge itself – as a mental exercise like Descartes did when writing his Meditations. Skepticism allows us to rid ourselves of our assumptions by forcing us to pretend that they don’t exist. By entertaining skepticism for a moment, one can then try to reason their way back to their initial assumptions to see if these assumptions make sense.

Theories dealing with the structure of justification/knowledge

Foundationalism. Unlike internalism and externalism, foundationalism deals with the structure of justification rather than its source. Foundationalism states that axioms, or basic beliefs which are self-evident, are necessary for our other justifications and beliefs. Simply put, there are some things that provide our foundation for justification as they are necessary for evaluating other beliefs. If this doesn’t make sense, you can imagine a child asking you a stumping “why” question, which leads them to ask another, and another. There will likely come a point at which their question can’t be broken down any further and not just because you don’t know the answer and the child is annoying you. Foundationalism helps deal with the absurdity which comes with the assumption that every justification needs a justification (called infinite regress in logic). The big question for someone who accepts foundationalism is mostly what sorts of justifications and beliefs are in fact foundational. Going back to Descartes again, the whole point of his exercise in knowledge skepticism was to (re)discover foundational beliefs. While he did find foundational beliefs, it’s entirely possible that the exercise could have just as easily led him to not find any.

Coherentism. Just as internalism is the rival to externalism, coherentism is the rival to foundationalism, and the debate between the two is another one of modern epistemology’s big discussions. While both fight away infinite regress, they do it in different ways. Coherentism judges how well a justification or belief validates other justifications and beliefs that relate to it. Foundationalism can be seen as a hierarchy with the important, untouchable basic beliefs sitting at the bottom. Coherentism is more like a mesh where there is no hierarchy at all. Beliefs and justifications support one another equally as they’re all simply related concepts which affirm one another.

Foundherentism. Foundherentism is an attempt to reconcile coherentism and foundationalism. The theory is mostly associated with Susan Haack, as she introduced it in her 1993 work Evidence and Inquiry: Towards Reconstruction in Epistemology. For Haack and some others, foundationalism and coherentism are prone to some degree of arbitrariness and circularity respectively. If you were to take the side of the coherentists, you might think that it’s not clear at all how one could determine that something is a foundational basic belief without making some sort of unjustified assumption. Similarly, for foundationalists, it’s not clear how using interrelated, coherent beliefs without reference to external justifications and beliefs is sensible. However, combining both positions, you get a set of beliefs that have an externally established foundation while being related to one another. Haack uses the analogy of a crossword puzzle to explain her theory — every entry must meet specified definitional criteria, but at the same time, each entry must agree in a way that multiple words can be spelled by connecting one entry to another. For some philosophers, though, it’s not clear how foundherentism differs from more moderate forms of foundationalism which loosen the criteria of what counts as a basic belief.

Infinitism. Infinitism is one of the possible implied conclusions that comes from the rejection of both coherentism and foundationalism. While the other two theories take a strong stance against infinite regress, infinitism is fine with the idea that all justifications need justifications. Infinitism in some form has been known at least since Aristotle who, like many philosophers, personally rejected it in favor of foundationalism. What’s interesting to note about infinitism is that it can imply skepticism. Basically, if justifications and beliefs are necessary for other justifications and beliefs, and human cognition is limited in a way that can’t comprehend infinite reasoning, then complete justified beliefs can’t exist and there is no basis for any justifications and beliefs. Those who advocate for infinitism seriously (a small handful of philosophers) acknowledge the mind’s limitations but still imply that an infinite chain of reasons can exist even if we can’t have epistemic access to the entire chain.

It’s important to note that some of these ideas aren’t mutually exclusive as they have different areas of focus. Internalism and externalism revolve around sources of justification and belief, fallibilism and skepticism revolve around certainty of belief, and foundationalism and coherentism revolve around the structure of justification and belief. So someone could be, for example, externalist about knowledge but internalist about justification. That same person could also be both fallibilist and foundationalist about justification.

What is true?

What is true? That’s a pretty big question, but since we’re talking about JTB here, it is important to point out that this question refers to epistemic truth or factive knowledge which limits the scope of the question. The conclusion that most epistemologists have come to is that known things cannot be false because knowledge only exists if beliefs are justified and true. “True” can then be thought of as a second condition modifying what belief is.

This might seem like semantics at first glance. What I mean is that, at least within JTB, knowledge is being defined in a specific way which necessarily excludes us from acknowledging false statements. It’s clear, though, that one can utter false statements, reflect on them, and imagine their implications — all of which seem to constitute some form of “knowing.” The distinction some philosophers make, however, is metaphysical or relating to the nature of reality. Since false things haven’t happened or haven’t been experienced, no one can have epistemic access to them. So to be able to contemplate false statements, or to know something is false, is not the same as claiming that you have knowledge about something that isn’t true and hasn’t happened.