Propositional Knowledge: Definition, JTB Model, Sources & Examples Explained

Have you heard about propositional knowledge? If yes, how is it unique or different from other forms of knowledge?

Since ancient Greece, knowledge has been at the center stage of investigation in philosophy. 

Epistemology that focuses on the source, nature, scope, and limits of knowledge is fundamental to propositional knowledge.

Propositional knowledge is all about a justified true belief that an individual acquires through testimony, reason, perception, and memory.

You will also read more on propositional knowledge in this article along with its sources, examples, theories, and values.

What is Propositional Knowledge?

Propositional knowledge entails knowledge of the fact that some proposition holds. This proposition is a statement that can either be true or false. 

As an illustration, the sentence The Taj Mahal is located in Agra conveys a proposition since it is a statement which can be verified about the world. When a person is aware of such a statement as true then the individual has propositional knowledge.

This kind of knowledge is normally expressed in the form “S knows p”. 

An example could be when a person says that Anita knows that the train arrives at 6 p.m., Anita is the subject and that the sentence that the train arrives at 6 p.m. is the proposition. The propositional knowledge is focused on the connection between truth and belief. 

A true proposition is inadequate when the subject lacks an appropriate epistemic relation to that truth.

This means a belief can become knowledge only when it goes through classical analysis and answers why it has to be believed. This is how propositional knowledge forms.

Propositional Knowledge and the Classical Analysis

Plato’s dialogue Theaetetus defines knowledge as true belief supported by valid reasoning, and classical analysis stems from this dialogue only. 

The concept developed as time passed, to be what is currently called the Justified True Belief model. On the basis of this analysis there are three conditions that are necessary and jointly sufficient for knowledge.

To begin with, the proposition must be true. There is the fact-based aspect of knowledge, that is, when a person knows something, the knowledge must be the case. 

When someone asserts that the earth is flat, their assertion does not pass the test since the statement is false. Knowledge thus must have truth as a requirement.

Second, the proposition must have a belief in the subject. It is paradoxical to say that an individual knows something, yet does not believe it. 

The psychological aspect of knowledge is belief, which is an acceptance of the subject on the proposition.

Third, the conviction should be warranted. Even a true belief could be constructed by a man by simple guesswork or chance, but that belief would not be a piece of knowledge.

Justification gives the rational basis which makes the difference between knowledge and guessing out of luck. It can be explained as possessing sufficient evidence or good reasons to believe something.

This three-part analysis was approved by philosophers as a sufficient solution to knowledge for many centuries. This agreement was however thrown into complete turmoil during the twentieth century.

The Justified True Belief (JTB) Model

The Justified True Belief model explains that an individual S knows p only when p is true, S believes that p, and that S has justification for believing p. 

This model seemed to be holistic as it touched the key elements of knowledge; truth, belief, and rational support.

For example, a student reads good, trustworthy textbooks, where they learn that an apple falls down due to gravity. The assertion is factual, the student has belief in it, and the faith is supported with valid evidence. 

The student is aware of this fact according to the model of JTB.

The JTB model is strong as it is based on its intuitive appeal.

 It embodies the principle that knowledge needs to be objective as well as subjective based on reasons. But, this model was doubted after Edmund Gettier wrote a short yet decisive paper in the year 1963.

Limitations of the JTB Model

Gettier provided the examples where all the three conditions of the JTB model were accomplished but the belief appeared not to be considered knowledge. 

In one of the examples given by him, Gettier cases involve justified but ultimately false premises that accidentally lead to true conclusions. Luckily, the belief happens to be true due to coincidental reasons. As much as this belief is true and justified, it seems to be true by mere chance.

These instances prove that justified true belief does not necessarily suffice to knowledge. 

The practical examples from Gettier pushed other philosophers to consider other conditions for defining knowledge. One such example was of a stopped clock, where the person looked at the clock and coincidentally saw the right time. 

Here, though the truth was justified, the knowledge was misleading.

Responses to the Gettier Problem

Gettier problems led the philosophers to suggest new contexts and even reconsider conceptual justification as a whole.

The No False Lemmas Theory

A solution that was brought forward was that knowledge should be a justified true belief but without any false assumptions. 

In Gettier cases, the reasoning of the subject is usually made on a premise, which is false, although the conclusion that occurs at the end is true. 

Philosophers hoped to block Gettier-style counterexamples by making the addition that knowledge should not be obtained by applying false lemmas.

Although this adjustment leads to a stronger analysis of the classical analysis, it does not address all the problematic cases. 

There are some examples demonstrating that a belief may be true by chance even in the cases when no false premise was used. Due to this, philosophers came up with more theories.

Reliabilism

Reliabilism changes our perspective on knowledge as it focuses on the procedure through which knowledge is proposed. 

If the belief is produced from a reliable source, it is more likely to be considered as knowledge.

Under reliabilism, a belief is considered to be knowledge when it is developed in a thought process that tends to give true beliefs. 

Perception in normal situations, logical reasoning, and memory are reliable ways of forming beliefs.

This method solves the Gettier problem by trying to focus on the causal relationship between the mental state of belief and the truth of the proposition. 

When there is a belief based on a trustworthy process it is unlikely to be accidental. 

Critics insist, though, that reliabilism counts beliefs as knowledge when the subject is unable to articulate why their belief is justified. This is an issue that questions intellectual responsibility.

Virtue Epistemology

Another powerful answer to the issues posed by Gettier is the virtue epistemology. 

Here, the emphasis is on the intellectual nature of the person, and not only the features of the belief, reflecting the influence of virtue ethics. 

Virtue epistemologists assume that knowledge is true belief when it is a product of an intellectual virtue of careful reasoning, open-mindedness, intellectual courage, and attentiveness.

Ernest Sosa and Linda Zagzebski have made the case that knowledge be treated as cognitive success due to the intellectual power of the subject. 

Moral virtue, just as it explains praiseworthy actions, has an intellectual counterpart, intellectual virtue, which explains successful cognition. 

In this system, knowledge is differentiated with lucky true belief since it is based on epistemic competence of the agent.

Virtue epistemology focuses on the importance of knowledge where it also relates it with personal excellence and responsibility. 

Sources of Propositional Knowledge

Propositional knowledge arises from the following sources:

1. Perception

One of the most basic sources of propositional knowledge is perception. Sensory experience lets people form beliefs regarding the external world. 

Observing a tree under daylight and thinking that it is a tree before them can be one of the most justified cases of perception. 

Perception is really essential in the formation of knowledge, though it can be misleading due to hallucinations and illusions.

2. Reason and Inference

Reasoning provides the opportunity to form knowledge from what’s already known by an individual. 

Deductive reasoning enables one to draw conclusions out of necessity. 

Inductive reasoning, the opposite, is concerned with probable generalisation from particular observations, the key aspect of scientific inquiry. 

By means of inference, people can broaden their experience beyond what they can see at the given moment.

3. Memory

Memory power retains the previously gained knowledge and enables the knowledge to be recalled with time. 

As an example, when a student knows that mitochondria is the powerhouse of a cell, and remembers this fact correctly, then the memory serves as a mode of preserving knowledge. 

Though, memory may turn out to be incorrect and its reliability can be questioned when not efficient.

4. Testimony

Much of the knowledge that humans have is from the testimony of other people. 

People depend on the teachers, specialists, reading, and media to acquire knowledge about the facts they have not checked themselves. 

Testimony plays a significant role in this process of transferring knowledge. 

The question that philosophers are arguing upon is whether or not testimony can be reduced to and derived from other sources, like perception and inference, or whether it is a primary and independent source of knowledge.

Propositional Knowledge vs. Other Types of Knowledge

Many philosophers compare propositional knowledge with two other forms of knowledge, which are procedural knowledge and acquaintance knowledge.

Procedural knowledge has been termed knowing how. An example could be when you are learning how to ride a bicycle or play a piano. 

This form of knowledge is not always defined by propositions. 

Someone may be a master of riding a bicycle, but might not be capable of explaining the steps involved. This proves that procedural knowledge is practical rather than being declarative.

On the other hand, there is acquaintance knowledge, knowledge of something or somebody. 

An example can be knowing a friend or a city where they have a first hand experience or direct familiarity with it. 

When someone says, I know Paris, they don’t mean that they are familiar with the city, they just know about the city.

The difference between propositional knowledge and these other forms is that it brings out statements as facts. It is interested in trustworthy claims, or statements which can be considered either true or false. 

An example of such propositions is The Earth revolves around the Sun. When an individual gets convinced that this is true and has suitably sufficient reasons to justify this truth, then they have gained propositional knowledge.

The significance of these distinctions lies in the fact that the nature of human cognition is complicated. 

Though propositional knowledge has been the most discussed form of knowledge in the field of philosophy, particularly in the fields of science and academics, procedural and acquaintance knowledge hold equal importance in daily lives.

Propositional Knowledge in Education

Propositional knowledge is important as a basic aspect in the formal education system. 

The majority of what is taught in schools and universities, is propositional, as they are historical facts, scientific laws, mathematical theorems, and conceptual definitions. These propositions are supposed to be learnt, comprehended, and backed by the students.

As an example, students in a history lesson are told that World War II ended in 1945. They are taught in a biology lesson that cells are the basic units of life. In mathematics, they can be told that in Euclidean geometry, the sum of all interior angles of a triangle is 180 degrees. 

The statements are propositions which are not only supposed to be memorized by the students, but are also supposed to be comprehended and explained using evidence or reasoning.

But, propositional knowledge is not the only one that constitutes education. It also includes procedural skills (e.g. solving equations or doing experiments) and acquaintance knowledge (e.g. becoming familiar with literary works or cultural practices). 

However, propositional knowledge is usually used as a basis on which the other types of knowledge are constructed.

In current education systems, it is also debated that our focus should be on skills rather than on factual knowledge. 

Some of the educational theorists argue that critical thinking and responsible citizenship can only be achieved through a good foundation of propositional knowledge. 

Lack of knowledge of important facts and principles can make students unable to analyze arguments, or even argue meaningfully.

Skepticism and Propositional Knowledge

One of the greatest challenges that exist against propositional knowledge is skepticism. 

According to philosophical critics, our thinking may be wrong and our faith may be false, questioning whether we can be certain about anything or not. 

As an illustration, if you are doubtful about how your nation’s media works, you might be skeptical about their claims, and hence not have real knowledge. 

Skepticism compels the philosophers to elaborate the criteria of knowledge. Should knowledge involve absolute certainty or must it be highly justifiable? 

The need to reach absolute certainty is denied by most modern epistemologists who reason that even fallible knowledge may exist. 

Thus, skepticism advances understanding of propositions, and highlights their flaws as well as the importance of justification.

It pushes philosophers to improve the criteria for determining what constitutes true knowledge.

Value of Propositional Knowledge

Propositional knowledge is of real value in people’s life as it has so many benefits like making them capable of making wise decisions. 

When individuals are aware of general knowledge related to their daily living, they automatically have better context for their decision making.

For example, students who know the advantages of good study habits would more likely follow a better schedule.

Propositional knowledge helps in taking actions towards technological developments and societal revolutions.

In democratic societies, the debate amongst people is based on common facts and evidence. 

With sound propositional knowledge, the citizens become aware enough to assess the policies, evaluate the claims, and achieve good civic life.

Knowledge is believed to have extra value when it is backed by reasons or trustworthy procedures. This is an extra element of justification which makes it reliable and useful.

Propositional Knowledge Example

Examples of propositional knowledge can be from any field or subject like mathematics, computer science, history, science, or geography.

• Humans and dogs are mammals.
• The sum of all the angles in a rectangle is 360 degrees.
• The blue color of the sky is due to Rayleigh scattering.
• Plants make food through the process of photosynthesis.

Belief Condition in Propositional Knowledge

Propositional knowledge is one of the fundamental concepts in the study of epistemology involved with the nature, sources, and boundaries of knowledge. 

Propositional knowledge is the most basic level of knowledge that defines if a particular statement or proposition is true. 

It is different from other types of knowledge since it deals with cognitive approval and validity of a claim. 

Philosophers have been arguing about what conditions are necessary to label a belief as knowledge and propositional knowledge has been the centre of the debate.

Belief as an element of propositional knowledge. A person cannot know without believing in the proposition. 

Unless a person believes that a proposition is true, we cannot say that he knows that proposition, even though the proposition may turn out to be true. 

Not all belief constitutes knowledge though. Numerous beliefs are false and they are not considered as knowledge. 

Therefore, propositional knowledge can only be understood by looking carefully at the interaction of belief, truth, and justification.

Conclusion

To put in simple terms, propositional knowledge is a true belief backed with facts and reasons.

In traditional schooling, propositional knowledge has been pursued for ages through transmission and testimony from teachers.

Though, there have been many changes in how we view propositional knowledge and shape its credibility through memory, perception, and evidence.

Propositional knowledge is still crucial and adds huge value in human lives.

Education