Epistemology, Concepts

Epistemology is the philosophical discipline that explains the nature of knowledge and identifies the principles by which knowledge must be gained, held, and used if it is to be true knowledge.

Epistemology, like all other disciplines, such as language, mathematics, the sciences, and all of philosophy, is a human developed method. There is no authority dictating the principles of epistemology. Like all other principles, the nature of epistemology must be discovered. What ultimately determines if epistemology is correct or not, is reality itself. Only an epistemology that explains how knowledge of reality is achieved, and makes it possible to know and understand that reality is a correct epistemology.

[NOTE: To "know and understand reality" does not mean to know and understand all of reality or everything about it. It does not mean omniscience or infallibility. It only means that which exists can be identified and understood and one's knowledge consists of all that one has identified and understands about that existence.]

What Is Knowledge?

The whole of epistemology would be required to answer the question of what knowledge is. Here the question only refers to what knowledge, in the epistemological sense, refers to.

The word knowledge is used to identify many different concepts, such as developed skills and abilities (he knows how to drive, she knows how to type, he knows how to play the piano), things one has experienced (I know what cinnamon tastes like) or is acquainted with (he knows where the library is) or even for things animals can do (Rex knows his way home).

Knowledge, in epistemology, refers only to the kind of knowledge possible to human beings, knowledge held by means of language. Language is a system of symbols called words which stand for concepts.

Knowing a language is not just being able to respond to a few sounds, signs, or symbols. Knowing a language means capable of forming, speaking, writing and understanding complete sentences. Knowing a language means being able to think, read, write, ask questions, and understand verbal explanations in that language.

The primary purpose of language is to gain and hold knowledge and to use that language to think, and make choices. A secondary derivative purpose of language is communication.

[NOTE: The primary purpose of language is not communication. The purpose of language is knowledge and thinking. One must know something before it can be communicated and must think it before it can be written or spoken. Since human beings are volitional beings they must consciously choose to think, write, or speak.]

The Purpose Of Concepts

Words, in any language, represent concepts. Concepts have a single function which is to identify existents. Existents are anything that exists, ontologically (materially), or epistemologically. Material existents (entities) and epistemological existents are all that exists. See, "Kinds Of Concepts," described below.

The Structure Of Concepts

A concept consists of two components a "perceivable existent," and a "specification." The, "perceivable existent," is a symbol, usually a spoken or written word. The "specification" is a definition which specifies or indicates the existent or existents the concept identifies.

The word (or other perceivable symbol) for a concept is not the concept. The word is our means of being conscious of the concept. The concept is the identification of an existent. The definition of a concept indicates what existent a concept identifies.

A concept is not an independent existent and does not exist as either a material (ontological) or psychological (epistemological) existent. A concept only exists as an identifier of existents with the specific structure of a word and its definition.


We can only directly perceive the physical—things that can be seen, heard, felt, smelled or tasted or experienced internally. We can see written words, hear spoken words, and feel words in Braille. Once we have seen, heard, or felt a word, that percept is stored in memory and we can recall it to perceive it without an 'external' source.

Though words can be written and read, spoken and heard, even signed and recognized, words, as components of concepts, are usually "mental" words, words as we think them recalled from memory. Written and spoken words are only marks on paper or sounds that represent the words we think. We first have to think a word before we can say or write it and a written or spoken word only has meaning if someone reads or hears it and mentally recognizes it. The marks on the paper and sounds in the air do not have any meaning. Their only function is to enable the reader or hearer to recall the meaning from memory.

Written and spoken words are symbols for the words we think, but words, as we think them, (except when we are thinking about them as words, their spelling for example), are part of concepts. It is words that provide the part of a concept we can be conscious of.

[NOTE: Concepts do nothing except identify existents. They do not represent existents, describe existents, or indicate anything about the existents identified. It is necessary to emphasize this to prevent criticisms of knowledge based on a wrong understanding of what concepts are. Statements, like, "we can never know anything completely because concepts are only incomplete abstractions representing actual things." Concepts are not abstractions, not "stand-ins" for existents, they are identifications of actual existents with all their qualities and all that can be known about them.]

How Concepts Identify Existents

If asked what he would like, a young boy wanting an apple might point to the apples in a bowl and say, "I'd like one of those, please." If there are no apples in plain sight, however, he might say, "I'd like an apple, please." The pointing and using the word apple have performed the same function—they have identified the kind of thing the boy wants.

It is not the word apple, but "using the word apple," that is the identifying action, because a spoken or written word is only a symbol, and it is the concept (symbol plus definition) that does the identifying. When the boy uses the word apple, he has already identified apples mentally before saying the word, else he could not say it. It is also not the spoken word that identifies an apple for the listener but the concept, apple, which hearing the word recalls to the listener's mind.

The identity of the apple is independent of anyone's knowledge or understanding of it. The apple's material identity is an ontological fact consisting of all an apple's qualities and attributes, known or unknown. To identify an apple by means of the concept "apple" does nothing more than pointing and saying, "one of those," does. The obvious advantage of a concept is that identifying an apple does not depend on the presence of a physical one. Because we can identify an apple anytime by means of the concept, we do not have to have any apples before us to think about them.


While identifying an apple by pointing at it, accompanied by the word apple, is referred to as an ostensive definition, and is most likely the way our earliest concepts are learned and defined. For adults, most concepts are defined verbally.

A verbal definition must specify what existent a concept identifies. For all entities it is the entities' material (ontological) nature that determines how concepts for those entities are defined. Since, ontologically, an existent is all its qualities, it is its qualities which are its identity, i.e., what it is. [See, "Ontology Introduction."]

It would be impossible to list all of an entities' perceived qualities, physical qualities, relationships, and behavior both, because there are too many and, most likely, not all are known. It is not necessary, however to list every possible quality of an existent to identify it epstimologically. It is only necessary to identify those qualities that are unique to that entity that differentiate it from all others, within the context of one's present knowledge.

How any particular concept must be defined is determined by what must be specified to identify the existents the concept refers to in whatever context that idenfication must be understood which will be determined by the limits of an individuals own knowledge and the field and context in which the concept will be used. The same conept may be correctly defined within one field but differently and correctly defined in another field, so long as that definition in that context isolates the identified existents from all others, thus indicating the same existents. A fisherman's guide might define a smallmouth bass descriptively as "a species of freshwater fish in the sunfish family with an elongated body, brownish-green in color fading to a yellow-white underside. Its sides are covered with dark brown vertical lines while its head has dark brown horizontal streaks. The dorsal fin appears to be divided in two, with nine spines on the front part. The jaw of a smallmouth bass extends to line up with the middle of the eye. The eyes of this type of bass are usually red," while a zooligist might use the taxinomical definition of a smallmouth bass as "a species of freshwater fish of the order, Perciformes, of the family Centrarchidae, and genus Micropterus and species M. dolomieu." Both definitions are perfectly valid because they both isolate the same existents identified by those concepts.

How different kinds of concepts are defined will be explained under, "Kinds Of Concepts."

It is not words that are defined. Words are not concepts. Words are only symbols that represent concepts. The words, 'home,' 'domocile,' 'residence,' 'abode,' 'casa,' (Spanish), 'maison,' (French), 'spiti,' (Greek), and 'ban,' (Thai) all have the same definition because those different words all stand for the same concept. It is not the symbols or words for concepts that have meaning, but the concepts the symbols represent.

The same word (symbol) may also be used to represent more than one concept. The word, 'light,' represents many different concepts for different existents, which may be related but are not the same existents, requiring different definitions, such as: "electromagnetic radiation that makes vision possible," "a source of light: such as a lamp," "enlightenment," "not dark," "to ignite a fire," "to illuminate something," "not heavy," "slight," "quick," "soft," "dismount," and "alight or land." Each is a different concept for a different existent represented by the same symbol, "light."

A word is not a concept. A definition is not a concept. A concept is a word and definition that together identify specific existents.

What A Concept Means

What concepts mean are the actual existents they identify. The existents identified by concepts are called a concept's referents, units, particulars, instances, or specimen. These terms may have slightly different conotations but are correct so long as it is the actual existents (ontological entities or epistemological existents) identified by a concept that is referred to.

The concept "apple" means any apple there has ever been, is now, or ever will be. As the identifier of apples, what it identifies is the entire ontological nature of any apple in its entire ontological context, because that is what any apple is. That nature and context are not part of or in any way contained in the concept, apple. The nature and context pertain only to what the concept identifies, that is, actual individual apples themselves. Therefore, what the concept apple means is any apple or apples with all their qualities and attributes and all that can ever be known about them, whether it is known or not.

The concept, apple, used by a child who knows little more about apples than what they look and taste like, or the same concept used by a botanist specializing in the study of apples, means exactly the same thing, actual apples. Neither the child's limited knowledge or the botanist's extensive knowledge is about the concept apples or part of the concept apples; the knowledge is about that which the concept identifies for both the child and the botanist, actual apples themselves.

Kinds Of Concepts

All concepts of any kind have the same basic function or purpose—to identify existents. Because existents are all different with different natures, there are different ways of forming and defining concepts, some more suitable than others for specific existents and purposes.

Six of the most common ways of classifying concepts are the following:

1. Material (or ontological) versus epistemological.
2. Particular versus universal.
3. Intrinsic versus extrinsic.
4. Analytic versus synthetic
5. Complex (anthropological) concepts
6. Concepts for categories, existents, qualities, actions, and relationships

Those categories that are contrasted (intrinsic versus extrinsic, for example) are exclusive of each other, but otherwise these categories are not exclusive and most concepts belong to more than one class of concept.

Material (or ontological) versus epistemological.

Everything that exists is either material or epistemological. All concepts that identify material existents, called entities, are material concepts. All concepts that identify non-material existents are dependent for their existence on the human mind and knowledge and are called epistemological concepts.

All concepts for physical entities, including all living physical entities (organisms), all conscious organism, all intellectual organisms (human beings) and their qualities, behavior, and relationships are material concepts.

All concepts for human intellectually developed methods and knowledge including language, the sciences, mathematics, logic, history, philosophy, religions, and arts are epistemological concepts.

Particular versus universal.

A particular concept identifies a single existent. Most particular concepts are proper nouns or identified as individual referents of a universal concept.

A universal concept identifies a class or category of existents. Most concepts are universal concepts. By class or category of existents is meant indefinite (open ended) collections of the same kind of existent.

Since it is an existent's qualities that are what an existent is, it is an existent's qualities that determine the kind of existent it is. Existents of the same kind are those with some of the same qualities.

If the existents are entities (material) the fact that some entities have some same qualities is an ontological fact, but that they are the same kind of entities is only an epistemological fact, based on the observation of the entities' ontological nature.

Intrinsic versus extrinsic.

The intrinsic versus extrinsic classification of concepts pertains only to universal concepts and is based solely on how concepts are defined. Intrinsic concepts are defined on the basis of an exitent's nature, the actual qualities that are intrinsic to that existent. Extrinsic concepts are defined on the basis of what is known about an existent, extrinsic to the actual existent. The referents of extrinsic concepts, if material, also have intrinsic qualities.

For universal concepts of things that are members of the same category because of something inherent in the existents themselves, like dog, planet, rock, or elephant, it is their very nature that is the same—they are intrinsic concepts. For universal concepts like Athenian, cook, or trinket, the sameness is something external to the existents identified by the concepts and is determined by things such as where one lives, what one does for work, or what something is used for—they are extrinsic concepts. See, "Intrinsic And Extrinsic Universals," below.

Analytic versus synthetic

Analytic concepts, are those concepts whose definition is the result of analyzing the existents identified to discover the qualities that best describe, differentiate, or define them. Analytic concepts are all material concepts.

[NOTE: Analytic versus synthetic concepts must not be confused with the very wrong idea of analytic versus synthetic propositions espoused by Kant and other philosophers.]

Synthetic concepts are created by combining qualities, actions, and relationships from actual existents (identified by analytic concepts). All creation, invention, hypothesis, and planning proceed by means of synthetic concepts. Synthetic concepts are all epistemological concepts.

[NOTE: Concepts for potential inventions are synthetic until and unless the invention is actually created. Once an invention actually exists, if it is a material entity, the concept for it is an extrinsic ontological concept, though the physical substances it is made of are identified by intrinsic analytic concepts.

The characters, places, and objects created for a work of fiction are all synthetic concepts and remain synthetic concepts even after the work of fiction is published. If published in the form of books, the books are identified by extrinsic concepts, but the material the books are made from are identified by intrinsic analytic concepts.]

Since synthetic concepts are synthesized from attributes of other concepts, their definitions consist of the attributes or qualities they are created from. They cannot be discovered by either science or philosophy. It is the reason why no language, logic, mathematics, or other man-made method can be discovered, but must be learned from others, from recorded knowledge of these things, or invented.

Complex (anthropological) concepts

Concepts that identify things which have no existence or meaning separate from human knowledge, interests, activities, or concerns and consist of ideas that must be defined by propositions identifying the human element the existent relates to and the nature of that relationship are complex concepts.

Some examples of complex concepts are: meaning, principle, possible, necessary, problem, mistake, integrity, urgency, emergency, success, failure, important, purpose, interest, critical, vague, ultimate, tenuous, implied, passion, threat, excellence, dignity, honesty, news, lost, hope, boredom, and nostalgia.

Concepts for 1. existents, 2. categories of existents (universals), 3. qualities, 4. actions (or behavior), and 5. relationships.

All five of these concepts—individual existents, categories of existents (universals), qualities, actions (or behavior), and relationships—identify existents. The first two—individual existents and categories of existents—identify existents in themselves, including whatever their qualities, actions, or relationships are. The existents identified by the last three—qualities, actions, and relationships—have no existence separate from the existents they are the qualities, actions, or relationships of; nevertheless, they exist, and are identifiable by their own qualities.

These five kinds of concepts are all the concepts there are. Each of all other kinds of concepts is also one of these. Each of these identify existents of an indefinite number and variety.

[NOTE: Existents and their qualities, actions (or behavior), and relationships are all that exists. This is a metaphysical fact.]

[NOTE: Some existents will have qualities we refer to as states, which are conceptually subsumed under qualities or actions. Measurements are qualities.]

Kinds of Things and Essence

Most concepts are universal concepts. A universal concept identifies categories or classes of existents or existents of the same kind.

What makes things the same kind of things? More importantly, what makes anything the kind of thing it is? The answer to the first question is their essence; everything with the same essence is the same kind of thing. It is the answer to the second question that is the explanation of what essence is.

Essence and Qualities

From ontology we know the identity of every existent is determined by three necessary conditions: 1. it must have some qualities, 2. it must be different in some way from all other existents; therefore, it must have some quality or qualities that are different from those of all other existents, and 3. every existent has some relationship to all other existents; therefore, it must have some quality or qualities it shares with all other existents.

Every existent identified by a universal concept has two kinds of qualities: necessary and possible.

Necessary qualities are all those qualities of an existent that it must have to be identified as the same kind of existent, and without which it would not be that kind of existent. The "necessity" only pertains to the epistemological recognition of those qualities and only means qualities an existent must have to be included as a referent of the concept.

Possible qualities are all the qualities an existent may have, but will be the same kind of existent whether it has those qualities or not. Every individual referent of a universal concept must have some quality or qualities that are different from the possible qualities of all other referents of the same concept.

A dog is a physical entity, a living organism, an animal, a mammal, and a canine. Physical, living, animal, mammal, and canine are all necessary attributes of the concept dog. If something had all these attributes except one, it would not be a dog.

A dog can have short hair, long hair, or no hair, a tail, no tail, be very big, or very small and exhibit individual patterns of behavior. Hair, tails, a certain size and variations of behavior are all possible attributes of a dog, but none are necessary; a dog will be a dog with or without them.

Obviously it is an existent's necessary qualities that determine the kind of existent it is and equally obvious that every existent with the same necessary qualities is the same kind of thing.

The essence of a thing, therefore, consists of all its necessary qualities. A dog is a dog because it shares with all other dogs the same necessary qualities, that is, those that are a dog's nature or identity.

The difference in existents of the same kind must be differences in possible qualities.

Every dog has some possible quality or qualities that are different from the possible qualities of every other dog. No two dogs can have exactly all the same possible qualities. (The differences can be pronounced or very slight.)

[NOTE: Essence is strictly epistemological. There are no ontological or material essences. Material entities which are referents of the same concept are recognized as the same kind of entities because they share some same (necessary) qualities. Those same qualities are identified epistemologically and are called the essence of the entities identified by the concept. Ontologically, they really have those same qualities but ontologically those same qualities do not constitute an attribute of those entities called an essence.]

[NOTE: The observation that many material entities have some of the same qualities is the basis for much scientific research to discover the exact nature of those similarities and the reason for and relationship between those entities. That research has led to the discovery of the nature of the chemical elements, biochemistry, diseases, heredity, the laws of physics, and much more.]

[NOTE: Universal concepts are not abstractions. Universal concepts identify existents that have some qualities that are the same (necessary qualities). Such existents are considered belonging to the same category or class of existents, because they all have the same "necessary" qualities. All the members of a universal class or category also have qualities that are unique (possible qualities) to each individual existent (called referents of the concept) else they would not be different existents. The different qualities are not, "left out," or, "abstracted," they are included by implication and included explicitly in each instantiation of the concept.]

"Referents" of Universal Concepts

A referent or referents of a universal concept will all have the same necessary qualities. The identity of any individual referent of a concept is all the qualities it has at any moment, both necessary and possible.

Individual (particular) existents also have both necessary and possible qualities. A particular existent's necessary qualities are all the qualities it has at any moment. A particular existent's possible qualities are those that can change over time; it's necessary qualities are those that cannot change without that existent becoming a different existent or different kind of existent.

For any individual existent, at least one of its necessary qualities, as that existent, must be a possible quality of all other existents identified by the same concept, and it must be different from the actual possible qualities of all other units of that concept.

All of an individual existent's necessary qualities are its essence as an individual existent.

Most individual existents are identified as referents of universal concepts. A liquid or some liquid is a referent of the concept liquid. A corpse is a referent of the concept corpse. A house, a cow, a memory, a lie, and a verb are all referents of their respective concepts house, cow, memory, lie, and verb. This may seem obvious for nouns, but it is true for all universal concepts, such as modifiers (adjectives and adverbs). Whenever something is described as difficult, difficult is a referent of the concept difficult. When anything is described as dangerous, red, mysterious, important, those modifiers are referents of their respective concepts dangerous, red, mysterious, and important. This is also true for concepts of actions (verbs). Whenever something is said to jump, run, lie, love, or desire, those verbs are referents of their respective concepts jump, run, lie, love, and desire.

Qualities, Relationships, Behavior

Ontologically, an entity's nature (what it is) are all its qualities. Epistemologically, an entity's conceptual identity are all its known qualities, but the entity as a referent of that concept is the actual ontological entity with all its qualities, known or unknown.

All that can be known about any kind of entity are what it is (the qualities it has), what it does (its behavior) and how it relates to all other existents (its relationships). It is an entity's nature as determined by its qualities that determine what behavior and what relationships to all other existents are possible to an entity. For all universal concepts, the identity of all entities of the same kind are all those existent's necessary qualities. Individual existents of the same kind are differentiated from each other by their possible qualities. Only qualities are intrinsic in referents of a concept. The behavior and relationships of referents of a concept are extrinsic, because the entities will be the same kind of entities no matter what their behavior or relationships are. In those cases where entities of the same kind are described as having qualities that are all necessary, such as atoms and subatomic particles, individual entities must be identified by differences in behavior or unique relationships, since there are no possible qualities.

Intrinsic And Extrinsic Universals

For all intrinsic concepts of material entities, the essence is defined in terms of the ontological or material identities of those entities.

For all extrinsic concepts, the essence is epistemological (based on what is known about the existents, such as their purpose, use, function, membership in some collection, residence or relationship to other things). If the units of an extrinsic concept are material, the material aspects themselves have intrinsic essences, but as units of an extrinsic concept, the units intrinsic material qualities, are only necessary qualities if they cannot be different (e.g. a Musician's human attributes are necessary qualities) but are possible qualities if they can be different in different units or referents of the concept (e.g. a drinking cup may be glass, ceramic, plastic, or some other material).

For example, I have many different kinds of spoons. They are all units or referents of the concept, "spoon." Their essence as spoons is, "a shallow bowl on a handle used to prepare, serve, or eat food." The necessary qualities are, "bowl," "handle," with the function of being used "to prepare, serve, or eat food." I'll call this essence, "spoonness."

The essence,"spoonness," is strictly epistemological. While bowls and handles are physical entities and those qualities are necessary to spoons, "spoonness" is not intrinsic to spoons, because there are other existents with bowls and handles, such as certain oars, fishing lures, and golf clubs. It is the function, "to prepare, serve, or eat food with," that differentiates spoons from all other things with similar physical characteristics.

I have spoons that are made of wood, others made of metal, and still others made of plastic. Wood, metal, and plastic are all intrinsic concepts; the essences of wood, metal, and plastic are material attributes, the necessary attributes of these substances are physical. As any of these essences is instantiated in spoons, they are only possible qualities, however, because spoons can be made from many different substances and still be spoons.

Concepts And Knowledge

Concepts identify the things all our knowledge is about. A concept, by itself, is not knowledge, however. A concept's only function is identification.

All human knowledge consists of propositions. A proposition is a statement that asserts something about an existent or class of existents. Knowledge is about things: about existence itself, about the existents that are existence, and about their nature, their attributes, their actions, and their relationships to each other. It is by means of propositions that state what is true about existents, their nature, attributes, actions, and relationships to each other that all knowledge is formed and held.

All supposed knowledge must be either true or false. Except by implication, no concept is either true or false. Concepts can be good or bad, that is, they may identify confused ideas, or be vague and poorly defined, or may identify what does not really exist, (as though it did), as most mystical concepts do. What those concepts identify are fictions, but the concepts are neither true nor false. A concept only identifies things, and is just as valid when identifying fictional things as when identifying actual things.

Only propositions can be true or false. For example, "Zeus is a god worshiped by the ancient Greeks," asserts something about Zeus. If what is being asserted is correct, the proposition is true; if what is being asserted is incorrect, the proposition is false. The assertion, in this case, is correct, therefore the proposition, is true, even though the concept "Zeus" identifies a fictional existent. The same concept can be use in both true and false propositions. "The phoenix is a common bird found in the forests of Colorado," is false, but, "the phoenix is a mythical bird of ancient Egypt," is true.

Since only propositions can be true or false, knowledge consists entirely of propositions; but all propositions are constructed of concepts, without which no knowledge would be possible. Concepts identify the existents all our knowledge is about. Technically, concepts are not knowledge, but a definition, if correct, is knowledge because it is stated as a proposition.

One might say, all correctly defined concepts constitute a kind of knowledge, but notice, it is really only the definitions that are the knowledge, not concepts as identifiers, which is their only function. Concepts imply knowledge, and most concepts would be impossible without knowledge, but attributing knowledge to concepts themselves is an epistemological mistake. It is that mistake that is the source of such confused ideas as those that suggest knowledge somehow changes the meaning of concepts, so that what a child means by an apple, and what a botanist means by an apple are different things.

See "Propositions."