Knowledge: Philosophical Foundations, Varieties, and Value

What does it mean to truly "know" something? While the term is used casually in everyday conversation, the study of knowledge—known as epistemology—is one of the most complex and enduring branches of philosophy. From the way we acquire information through our senses to the structured ways we organize beliefs, the nature of knowledge touches every aspect of human existence.

Coin showing the owl of Athena — The owl of Athena, a symbol of knowledge in the Western world

: The owl of Athena, a symbol of knowledge in the Western world

Key Facts

Justified True Belief (JTB): A traditional definition of knowledge requiring truth, belief, and justification.
The Gettier Problem: A philosophical challenge suggesting that justified true beliefs are not always sufficient for knowledge.
Varieties of Knowledge: Includes propositional (knowing that), procedural (knowing how), and acquaintance (knowing by experience).
Epistemic Structures: Theories like foundationalism and coherentism explain how beliefs support one another.
Knowledge Economy: A modern approach to generating economic value through the use of knowledge.

The Definition and Analysis of Knowledge

For much of academic history, knowledge has been analyzed through the lens of justified true belief. Under this framework, for a person to possess knowledge, three conditions must be met: the statement must be true, the person must believe it, and there must be sufficient justification for that belief.

Venn diagram of justified true belief — The definition of knowledge as justified true belief is often discussed in the academic literature.

: The definition of knowledge as justified true belief is often discussed in the academic literature.

The Gettier Problem

In the 20th century, the traditional definition was challenged by what is now known as the Gettier problem. This concept demonstrates that it is possible to have a belief that is both true and justified, yet still fails to count as knowledge because the truth of the belief relies on luck or coincidence rather than the justification itself.

Venn diagram of justified true belief that does not amount to knowledge — The Gettier problem is grounded in the idea that some justified true beliefs do not amount to knowledge.

: The Gettier problem is grounded in the idea that some justified true beliefs do not amount to knowledge.

Kinds of Knowledge

Knowledge is not a monolithic concept; it manifests in several distinct forms depending on how it is applied and understood.

Propositional and Declarative Knowledge

Propositional knowledge, often referred to as "knowledge-that," involves knowing facts or truths about the world. This is frequently expressed as declarative knowledge, which can be recorded and stored in various formats, such as books.

Photo of the Totius Latinitatis Lexicon by Egidio Forcellini, a multi-volume Latin dictionary — Declarative knowledge can be stored in books.

: Declarative knowledge can be stored in books.

Procedural and Non-Propositional Knowledge

In contrast to knowing facts, knowing how refers to procedural or non-propositional knowledge. This involves skills and abilities, such as the physical coordination required to ride a bicycle.

Photograph of someone riding a bicycle — Knowing how to ride a bicycle is one form of non-propositional knowledge.

: Knowing how to ride a bicycle is one form of non-propositional knowledge.

Knowledge by Acquaintance and Testimony

We also distinguish between knowledge by acquaintance—direct, experiential familiarity with a person, place, or thing—and knowledge by testimony, which relies on information provided by others, such as witnesses in a legal trial.

Photos of the five senses — Perception relies on the senses to acquire knowledge.

: Perception relies on the senses to acquire knowledge.

Photograph of a person giving testimony — Knowledge by testimony relies on statements given by other people, like the testimony given at a trial.

: Knowledge by testimony relies on statements given by other people, like the testimony given at a trial.

The Structure and Acquisition of Knowledge

Philosophers also investigate how our beliefs are organized. Foundationalism suggests that knowledge is built upon basic, self-evident truths, while coherentism argues that beliefs are justified by how well they fit into a logical, interconnected system. Infinitism offers a third perspective, suggesting an infinite chain of justification.

Diagram showing the differences between foundationalism, coherentism, and infinitism — Foundationalism, coherentism, and infinitism are theories of the structure of knowledge. The black arrows symbolize how one belief supports another belief.

: Foundationalism, coherentism, and infinitism are theories of the structure of knowledge. The black arrows symbolize how one belief supports another belief.

Methods of Acquisition

Knowledge can be acquired through various channels, including perception (using the senses), reason (logical deduction), memory, and introspection (examining one's own mental states).

Skepticism and the Limits of Knowledge

Not all philosophers assume that knowledge is easily attainable. Skepticism is the philosophical position that questions the possibility of certain knowledge. From ancient skeptics like Pyrrho to modern debates regarding the reliability of our senses, the question of whether we can truly know anything remains a central theme in epistemology.

Bust of Pyrrho of Elis — Pyrrho was one of the first philosophical skeptics.

: Pyrrho was one of the first philosophical skeptics.

The Value and Transmission of Knowledge

Knowledge holds immense value, both intellectually and economically. In the modern era, the knowledge economy focuses on generating value through information and expertise. Furthermore, the transmission of knowledge across generations is a fundamental aspect of human culture and education.

Sculpture showing a torch being passed form one person to another — Los portadores de la antorcha (The Torch-Bearers) – sculpture by Anna Hyatt Huntington symbolizing the transmission of knowledge from one generation to the next (Ciudad Universitaria, Madrid, Spain)

: Los portadores de la antorcha (The Torch-Bearers) – sculpture by Anna Hyatt Huntington symbolizing the transmission of knowledge from one generation to the next (Ciudad Universitaria, Madrid, Spain)

Photo of early childhood education in Ziway, Ethiopia — The value of knowledge plays a key role in education for deciding which knowledge to pass on to the students.

: The value of knowledge plays a key role in education for deciding which knowledge to pass on to the students.

Historically, the spread of knowledge was revolutionized by technological advancements, such as the invention of the printing press, which allowed written materials to reach a much wider audience.

Photo of a replica of the printing press created by Johannes Gutenberg — The invention of the printing press in the 15th century greatly expanded access to written materials.

: The invention of the printing press in the 15th century greatly expanded access to written materials.

Oil painting showing Saraswati — Saraswati, the goddess of knowledge and the arts in Hinduism

: Saraswati, the goddess of knowledge and the arts in Hinduism

Summary of Epistemic Concepts

Overview of Key Epistemological Terms
Concept	Description
Epistemology	The philosophical study of the nature, origin, and limits of knowledge.
Justification	The grounds or reasons that support a belief.
Omniscience	The property of possessing maximal or complete knowledge.
Knowledge Falsification	The deliberate misrepresentation of known facts.
A Priori	Knowledge that is independent of experience (e.g., through reason).
A Posteriori	Knowledge derived from sensory experience.

Frequently Asked Questions

What is the difference between knowing "that" and knowing "how"?

Knowing "that" (propositional knowledge) refers to understanding facts or truths, such as knowing that water freezes at 0°C. Knowing "how" (procedural knowledge) refers to possessing a skill or ability, such as knowing how to play a musical instrument.

What is the Gettier problem?

The Gettier problem refers to scenarios where an individual has a justified true belief, but the truth of that belief is due to luck rather than the justification provided, suggesting that JTB alone is not enough to constitute knowledge.

How does foundationalism differ from coherentism?

Foundationalism posits that knowledge rests on a base of fundamental truths that require no further justification. Coherentism, however, suggests that a belief is justified if it is consistent with and supported by a wider system of other beliefs.

What is the knowledge economy?

The knowledge economy is an economic system in which the production, distribution, and use of knowledge are the primary drivers of value and economic growth.

Can we know things without using our senses?

Yes, through a priori reasoning. This involves gaining knowledge through logic and intellect independently of sensory experience, such as mathematical truths.