Selections from: THE PROBLEM OF KNOWLEDGE

No one seriously doubts that human beings possess what is termed "knowledge" considered as a subjective state of mind. We all know that we know something. We have spontaneous convictions which seem to us to be obvious facts. We don't question them. They produce in us a state of subjective certitude.

This is not enough, however, for the professional philosopher and should not be enough for the serious thinker. What we should want is to establish that this subjective certitude is grounded on objective reality. This is a vital question. This problem has generally been called the problem of knowledge or the epistemological problem. Epistemology is that branch of philosophy which deals with the validity of knowledge and the criterion of truth.

 Convictions Based on Sense Perception

We begin with sense-perceptions, those phenomena which no one can seriously deny. Our senses of sight, taste, smell, hearing and touch are our first contact with an outside reality. The ordinary person is certain that these senses reveal to him his own body and other bodies which are real in the world of physical objects.

Besides these senses which acquaint us with the outside world, the human organism also possesses what we may designate as internal senses. They enable us to apprehend facts of a subjective character in a sensuous manner. For instance, the common or central sense makes us aware of our sense-acts, is the seat of sense-consciousness, and notifies us of the presence of the perceptive acts mentioned above. The central sense allows us to distinguish in a concrete way between the various sense organs and sense perceptions and to locate them in the bodily system.

There is also an internal sense called imagination. The imagination uses the material supplied by our sense-perceptions to form images of its own fashioning, such as when we dream. It is through the imagination that we create, for example, a world of fantasy which exists nowhere but in our mind.

There is also sense-memory which recalls perceptions and events and recognizes them concretely as having been experienced before. We can remember persons and objects and the time and place of seeing them.

There is also a sense sometimes called instinct which does not play a prominent role in man's life, but is found to play a dominant part in the life of the "lower" animals. The influence of instinct is noticed primarily in actions which are necessary for the preservation of the individual and of the race.

All these senses convey knowledge of the reality of the physical world in some form or other and are the starting point in discussing intellectual knowledge. Again, no one seriously questions the spontaneous convictions which arise as a result of our sense-perceptions.

 Convictions Based on Our Intellect

Now we come to the matter of intellectual knowledge. This is distinctly "human" knowledge because we do not find it in other than the human being. Intellectual knowledge appears in three phases: ideas, judgments and inferences. The existence of these three phases is a fact of human existence and they lie at the very core of the problem of knowledge.

The definition of idea is that it is the intellectual representation of a thing. It is important to note that an idea of a thing is very different from a sense-perception of that thing. The senses perceive a thing in its concrete individuality with all the peculiar traits and characteristics which make this thing to be this thing and differentiate this thing from every other thing. An idea, however, apprehends a thing in those essential attributes which the thing has in common with all other things of the same class or species. It leaves aside all the individualizing and differentiating marks peculiar to the thing itself.

Let's look at a simple example to illustrate the above. I see a maple tree of a certain size, age, color, texture, shape and so on. My picture of this particular maple tree is the result of perception through the sense of sight. But the idea of tree is substantially different. I disregard all the peculiar elements of the individual tree and apprehend instead those essential attributes which it has in common with all other trees. My intellect combines them into a single intellectual image or idea, namely, a tree is a "woody perennial plant with a single main stem, usually about at least ten feet high." Sense-perception represents the tree in the concrete; the idea represents the tree in the abstract.

The definition of judgment is that it is an act of the mind affirming or denying one idea of another. Three factors are involved in the making of a judgment:

The intellect, for example, consciously apprehends and compares the ideas "tree" and "plant" and finds they agree. Then it pronounces this agreement in a judgment, "the tree is a plant." Conversely, comparing the ideas "tree" and "animal," the intellect perceives they do not agree and makes the judgment, "the tree is not an animal." If the assertion in the judgment is correctly made, it is a true judgment. If it is incorrectly made, it is false. Thus judgments contain truth or error.

The judgment is extremely important in the problem of knowledge because it contains the characteristic of truth or error. Sense-perceptions present or represent things concretely and ideas represent the essence of things abstractly. Judgments, however, claim to express the truth about reality as it actually is in itself.

The intellect does not always perceive the agreement or disagreement between two ideas by a direct comparison of the two. It cannot always make an immediate judgment about the two ideas. If, however, the mind can bring in a third known idea with which, upon comparison, the mind finds the two ideas to agree, then the intellect is justified in saying that these two ideas agree with each other. This is inference or reasoning and is defined as the mental process by which, from certain truths already known, the mind passes to another truth distinct from these but necessarily following from them.

That we reason and make inferences is a fact of everyday experience. And we are generally convinced that these inferences, since they consist of judgments and lead to a final judgment, are a valid form of knowledge and contain truth regarding reality as it really is. No matter the topic of debate, if we are sincere and not playing mere mind-games, we always debate with the conviction that these arguments can lead to truth and valid knowledge.

 Different Classes of Truths

Truth lies in the judgment. But not all truths are of equal value to man. Let's take a look at the various classes of truths.

We possess a class of truths which are analytical judgments. These judgments contain truths directly evident to the intellect through a comparison or analysis of the ideas of the judgment. There is no immediate sense-perception and no logical reasoning. They do not need a demonstration to verify them.

For example, the judgment that "the whole is greater than any of its parts," is known directly by the intellect through an analysis of the ideas contained within the judgment. No proof is necessary and, indeed, in many cases, no proof is possible. There are also some axioms which are judgments of the analytical variety and constitute the basic principles which are at the bottom of all knowledge. Axioms like the principle of identity (A is A) and the principle of contradiction are used in every act of reasoning and are universally, necessarily and absolutely true.

We also possess a class of truths which are immediate judgments containing truths which are derived from direct experience through internal and external sense-perceptions. Such judgments refer to individual concrete facts, events, persons and objects.

For example, the judgment that "that cat is running," cannot be known simply by comparing or analyzing the ideas of "cat" and "running." The cat could just as well be playing, scratching or whatever. That I can actually judge "that cat is running," is because of my actual experience of seeing the cat run. This type of judgment is not analytical, it is synthetic. It contains empirical truths based on direct experience. Such judgments are not considered to be universal, necessary or absolute. They are contingent and experiential truths which may change with changing circumstances.

There is another class of truths called mediate judgments which are deduced by inference or reasoning from first principles. These judgments are based on self-evident first principles or axioms, but are not self-evident themselves. It takes a process of reasoning to show that such judgments follow necessarily from the axioms.

For example, the judgment that 38,400 is divisible by 2,560 fifteen times is not in itself immediately observed. If, however, we perform the division or multiply 2,560 by 15, we can prove the truth of the judgment. Mathematical deductions are examples of mediate judgments deduced by inference. Provided that our reasoning powers are essentially valid, mediate judgments derived from first principles are universally, necessarily and absolutely true.

A fourth class of truths are mediate judgments which are the result of an inductive process generalizing the individual, concrete data of direct sense-perception into laws of a universal character. The laws and generalizations of experimental science are of this type.

For example, the judgment that "the boiling point of water is plus 212 degrees F. at sea level," is an example of a generalization (or law) made through an inductive process. This process depends on careful investigation and extensive experimentation.

The above discussion constitutes a survey of the sources and main facts of knowledge as revealed in the spontaneous conviction of men. There is one trait characteristic of these spontaneous convictions, namely, our knowledge is a faithful and genuine representation of reality as it is in itself.

Ideas are the building blocks of knowledge. Judgments, which are expressed in sentences called propositions, are made up of ideas. A judgment is an act of the mind pronouncing the agreement or disagreement of ideas among themselves. We need, therefore, to direct our attention to what ideas are and how are they formed.

We can begin to understand the nature of the idea by taking a look at the process we use in forming ideas. The process which is described here is a philosophical process, from the viewpoint of common sense critically examined, and not one described in the terms of the physical and biological sciences. So pay particular attention to the definition of the words used.

All knowledge begins with the senses. We perceive many objects out there in the world which are presented to our various senses. For example, we see a lump of sugar and say it is white in color. We touch it with our fingers and notice it is granular in texture. We taste it and discover it is sweet. This combination of white, granular, and sweet forms a sense image in us which is retained in our imagination and memory. We can recall this image even when the object is not present before us. If we hear the word "sugar," we can recall the image of sugar. (Consult the chart below on Sense Knowledge.)

The same thing applies to other words in a similar way. When we hear words like "mountain," "dog," "John Wayne," and so forth, we can recall their image as long as we have perceived them in fact or have heard or read about them. When my little dog, Ming, hears the word "treat" he immediately begins to jump and bark. This is the word he has associated with the little dog bones he gets now and then as a special favor. By means of his memory and imagination, he recalls the image of the bones that he has previously experienced.

This sense image of the imagination is the first step in the formation of an idea.

Now that the sense image is in the imagination, the mind begins to think and the intellect gives its attention to the sense image in order to make its own representation of the object. It does this by a process called abstraction. Let's take an example of this process in action so this matter will be clear.

Through experience we come into contact with objects which we designate by the word "dog." One thing we discover right away is that there are a great many differences among the dogs we experience. Some are large, some are small. Some are fat, some are thin. Some are black, some are brown, and some are another color. Some are old, some are young. Some are male dogs, some are female dogs.

The intellect notices these differences and discovers that some of these characteristics change or disappear, while others take their place. But the intellect also realizes that some characteristics remain intact throughout all the changes. For instance, all dogs have a body, take in nourishment and water, and have physical senses enabling them to experience the world around them. The intellect notices that dogs are living, sentient, and conscious substances. The word "substances" means a thing that exists in itself. Dogs are substances, as are human beings, desks, rocks, plants, and so forth.

It doesn't matter what color a dog is or whether the dog is large or small or has a mean temperament. There are some things that make a dog to be a dog and those things we call the essential elements which constitute his nature. A dog must be sentient to be a dog. This is a characteristic essential to be a dog. A dog is a living substance made from chemical materials. These are essential to be a dog.

Once the sense image is formed and registered in the imagination and memory, the intellect strips the individual dog of all the nonessential characteristics, retains the essential characteristics only, forming them into what is called an intellectual image. The intellectual image of a dog is that it is a sentient, living, bodily substance. This intellectual image of a dog is the idea of dog.

We form the idea of "man" or "human being" the same way. Our experience brings us into contact with many beings which we designate by the word "man." We notice differences among these many beings but we also recognize some similarities. When a particular human being is sensed, a sense image is formed and from this sense image the intellect abstracts the essential characteristics, forming an intellectual image or idea of what is necessary to be a "man" or "human being."

Human beings differ in many nonessential characteristics. Just like dogs, some human beings are tall or short, fat or thin, white or black or brown, healthy or diseased, and so on. But what is it that all human beings have in common? What are the essential characteristics to be a human being? Certain characteristics are obvious. Human beings are a substance, that is, an independently existing being, and they are made of living material and are sentient. All human beings must have at least these essential characteristics to be human. But dogs and other animals also have these characteristics. So how do we differentiate human beings from other animals?

There is one essential characteristic that human beings possess that animals do not. (It should be noted here that while human beings share certain essential characteristics with other animals, human beings here are considered to be different in kind from other animals.) This essential characteristic is rationality. Rationality refers to the ability to form abstract ideas, to reason intellectually, to form moral judgments, and so on. So far as we know, animals do not possess these abilities.

The essential characteristics of a human being are that of a substance that is material, living, sentient, and rational. Since animals are also substances that are material, living, and sentient, and the only difference between animals and human beings is the essential characteristic of rationality, philosophers have traditionally referred to the human being as a rational animal.

Let's consider plants for a minute. We experience a variety of plants we call "trees." How do we form the idea of a tree? Once the sense images of these plants is available to our intellect, it ignores the differences among them as to size, shape, color, and other nonessential characteristics. The intellect retains the essential elements, those things that are found in all trees, and combines them into a single intellectual image or idea of "tree."

We are now ready to define the word "idea." An idea is the intellectual image or representation of a thing. Another word for "idea" is "concept."

The idea must not be confused with the sense image. The sense image is formed in the imagination as a result of sense data. We see, hear, feel, smell, or taste something and form a sense image. The idea, on the other hand, is formed in the intellect.

The sense image is always concrete, individual, particular. We cannot form a sense image of all members of a class of individual objects. Our imagination can make a general picture of a black dog, for instance, but it cannot make a sense image that will fit a black dog and a white dog at the same time. The sense image will fit either a black dog (a particular) or a white dog (another particular) but not both.

No single sense image of "man" or "human being" can adequately fit at the same time a baby, a teenager, an old woman, Thomas Jefferson, or Socrates. No single sense image of "animal" can fit an amoeba, a spider, an elephant, a salmon, and a dinosaur. The reason for this should be clear. The senses picture single, concrete, particularized objects. The imagination makes the sense images from these sense pictures. So the sense image must also be concrete, individual, and particular.

The idea or concept is different. The idea can apply equally to an individual and to a class of individuals and even to a number of classes of individuals. We say the idea is universal. The idea "human being" can fit a baby, a teenager, an old woman, Thomas Jefferson, and Socrates. No problem. The idea "dog" can fit a German shepherd, a dachshund, a great Dane, and even my little Lhasa Apso, Ming. No problem. The idea of "human being" and "dog" can apply to a single individual of the class or to the entire class of individuals itself.

Another difference between the sense image and the idea is that the sense image becomes very vague and indistinct when it becomes complex and has to deal with a multitude of detail. We can form a sense image of five people in a row. But to imagine five million in a row is virtually impossible. The idea of five million people, however, presents no problems and is as clear as the idea of five people.

Still another difference between the sense image and the idea is that we can have a very clear idea of some things for which we cannot reasonably form a sense image. For example, we often talk about such things as the "law," or virtue, or life, or justice, or, for that matter, logic. How does one form a sense image of such things? We do not even attempt to do so. We simply think and talk about virtue, justice, logic, and so forth, without worrying about a sense image of them.

THE NATURE OF IDEAS (Con't) 

The comprehension of an idea is the sum total of all the attributes or thought-elements which constitute the idea in its representation of a thing. Sometimes this is also referred to as the connotation of an idea. The comprehension or connotation of an idea gives the content of the idea.

Let's take our idea of "human being" for an example. What elements are important? Human beings are a substance with a material body that is living, sentient, and rational. The elements&emdash;substance, material body, living, sentient, rational&emdash;form the comprehension of the idea of "human being." This tells us what a "human being" is. A plant is a living material substance. This is its comprehension. An animal is a sentient living material substance. This is its comprehension.

 The Extension of the Idea

The extension of an idea is the application of this content to the individuals and groups in which it is found. It is the sum total of all the individuals and groups to which can idea can be applied. For the idea of "human being," the extension will include each and every individual which is a human being, from the first human being to the future human being. For the idea of "dog," the extension will include each and every dog that ever existed and will exist in the future. Sometimes the extension of an idea is called its denotation.

A couple of things need to be said at this point so there's no confusion. First of all, an idea can refer to something which has no actual existence other than in your mind. We can have ideas of dragons and unicorns, for example. The extension of these ideas would include all the dragons and unicorns that were ever thought or described. Secondly, some ideas may have an extension which includes only a single individual. The idea of "the tallest building" can have no more than one member in its extension. The same holds true for such ideas as "the highest mountain," "the strongest man," and "the last state to join the United States."

We must also be careful sometimes about how we apply the extension of an idea. Language and custom may cause confusion. We may use an idea which ordinarily signifies an entire class of individuals but which we may not mean for it to do so. We may make a statement in which we really mean to include only a limited portion of the extension of an idea. When I was growing up in a Dutch community, it was not uncommon to hear Irish neighbors say "The Dutchman is a stubborn person." I don't think they intended to convey the idea that each and every Dutchman was stubborn, but that many of them were. This is a use of language which must be watched in the course of an argument. It has to be realized that the extension of the idea of "Dutchman" is being limited in this case. Logicians call this limitation of the extension of an idea the universe of discourse. It has no value for logicians since it is arbitrary and subject to mere convention.

 The Relation Between Comprehension and Extension

Usually logicians say that the comprehension of an idea can be neither increased nor decreased without changing the idea itself. This is especially true when we consider class-ideas where the comprehension is clear and fixed. The comprehension simply contains the essential elements of the class. If an essential element is taken away, it would certainly change the whole idea of the thing.

Consider again the idea of "human being." The essential elements are substance, material body, living, sentient, and rational. Take out any one or more of these essential elements and what happens? Well, we don't have the same idea of "human being" anymore, do we? The idea of "human being" is clear and fixed and if its comprehension is increased (by adding an additional element) or decreased (by taking an element away), the idea is not the same as it was before.

Unfortunately, we don't always have a clear and fixed comprehension of every idea. Take, for instance, the idea of "virus." We simply don't know at this time whether a virus is a plant-form or an animal-form. A virus exhibits characteristics which cause some confusion. Botanists and zoologists both claim it for their study. So the idea of "virus" is not so clear and fixed at this time.

The comprehension of the idea of "whale" used to include that of "fish." This was once considered an essential element of the idea. (Remember how the biblical story of Jonah was first presented to you?) But science came along and proved that the whale is really a mammal. So the element of "fish" had to go and the essential element of "mammal" entered into the comprehension of "whale."

It seems that the farther we go from the broad classes in nature and the closer we come to particular individuals, the more difficulty we experience in uncovering the really essential elements which distinguish one from the other. Our ideas in these cases may not be fixed and clear and exact. We are making new discoveries all the time and that shouldn't bother us at all.

Regardless of what has been said above, the general rule of comprehension still holds. The comprehension of an idea can be neither increased nor decreased without changing the idea itself.

There is a similar rule about the extension of an idea. This rule says that an idea can be increased or decreased without destroying the idea. This simply means that the comprehension of an idea can be applied to more or fewer individuals without any change in the idea as such. The idea of "human being" will remain the same whether it includes one individual or millions of individuals. The idea of "dog" will remain the same whether it includes all dogs or just my Lhasa Apso, Ming. Trees and weeds die, but the ideas of "tree" and "weed" continue on without change.

There are two general rules in considering comprehension and extension, or connotation and denotation. The first rule says: The comprehension of an idea always remains the same, while the extension of the idea may change continually.

The second rule says: As the comprehension of an idea increases, the extension of the idea decreases; and as the extension of the idea increases, the comprehension of the idea decreases.

The chart below may help you understand these general rules.

The so-called "Problem of the Universals" has been a controversial topic in modern philosophy. Controversy aside, however, universal ideas are of the utmost importance for philosophy and science. The particularities of the controversy need not concern us here and the arguments regarding their philosophical status are highly technical and beyond the scope of this discussion.

We will simply accept the necessity of universal ideas. Without universal ideas it would be difficult to see how we could discuss philosophic and scientific theories since universals are the very foundation upon which philosophy and science rests. Our presentation here is in accord with the conception put forth previously; we are dealing with matters of common sense critically examined. We accept that there is a real world out there and that we can know it directly in some manner.

The comprehension of a universal idea applies to a class as a whole and also to each and every member of that class. Our idea of "human being" applies to each human being taken individually and also to all human beings taken together as a class.

It would seem, then, if the universal idea of "human being" is a true representation of human beings as they are in reality, that "human being" has a nature which is single in each individual and one in the whole class of human beings. The nature of human being would be one since it applies to a class as a whole, while it would be multiple since it applies to each individual member of the class.

This seems to a contradiction. How can it be one and multiple at the same time? Such a contradiction would invalidate the universal idea as a true representation of things. This problem, however, is easily overcome.

When we look about our world, we perceive individual, single objects, each consisting of individual natures. There are over five billion human beings on planet Earth, each possessing his or her own individual nature. Each nature possesses many characteristics such as height, color of eyes, emotional temperament, bodily structure, and so on. No two human beings are perfectly alike in all characteristics and this is why we can distinguish one human being from another.

Our senses perceive individual human beings and from these sense perceptions we form a sense image which represents each individual human being, including all the individual characteristics or attributes which are part of that individual. Jane is different from Sally, John is different from Peter, and we perceive the differences. We form one sense image of Jane, one of Sally, one of John, and one of Peter. These are concrete, particular individuals.

Our intellect, however, when considering each sense image, realizes that there is something permanent and common to all these individuals. While recognizing that Jane, Sally, John, and Peter are different individuals, the intellect realizes that some characteristics are always present in each and every individual. There is something that makes each of these individuals to be what they are, that is, members of the class of human beings. Such characteristics constitute the nature or essence of the individual.

Human beings are substances with living material bodies who are sentient and capable of rationality. Since we share with animals the characteristics of substance, living material body, and sentience, and the only difference between human beings and animals is the characteristic of rationality, we can refer to the essence of human beings as "rational animal."

What is it that distinguishes a human being from any other thing? It is the capability to be rational. To be a human being means to be a "rational animal." If these characteristics are missing, there is no human being. Jane, Sally, John, and Peter share this essence or nature. The intellect recognizes this common nature and puts these individuals into the class of human beings.

The intellect also recognizes the differences among these individuals. Jane has blonde hair, Sally has blue eyes, John is taller than Peter, and Peter has a dark complexion. But any of these characteristics may be absent or different and it would not change the essence or nature of the individual. Jane could have blonde hair or black hair and Sally could have blue eyes or green eyes. Regardless of these differences in attributes, Jane and Sally share in common the fact that they are "rational animals."

What has been said above gives us the basis for the origin and validity of universal ideas. The sense image represents the individual in all its concrete characteristics and differences. The intellect abstracts from this sense image the essence or nature which is common to all the members of a class, leaving aside the characteristics which distinguish them from one another. This essence or nature is a reality that is really present in the individuals and is independent of our intellect.

The intellect includes this essence or nature in a single idea which is a true representation of the essence or nature. Furthermore, the intellect recognizes this essence or nature as being the same with the sameness of a perfect likeness in each individual taken singly and in all individuals taken as members of a class. In other words, the intellect recognizes that the comprehension of the idea of "human being" will apply to the class of "human beings" taken as a whole, and also to each individual as a member of the class of "human beings." This is what a universal idea is.

The universal is a true representation of things as they are in themselves. The universal simply leaves out of consideration all the characteristics and attributes which are different to each individual member of the class. It doesn't matter whether we are considering Eskimos and Pygmies, African-Americans and Native Americans, white Europeans and Arabs. All of these peoples, while differing in many respects, have, individually and collectively, one common essence or nature. This idea of the common essence, since it applies to all, individually and collectively, is a true universal.

It is important to remember that there is no really existing universal essence or nature in the things themselves. Jane, Sally, John, and Peter do not actually share in one universal essence or nature. Each one of them possesses his or her own individual essence or nature distinct from that of other human beings. The universality of the universal idea is a product of the intellect, which has the power to recognize the common essence or nature in the various individual members of the class of human beings.

 Direct Universals: Categories

A direct universal considers and manifests only the comprehension and the intellect pays no attention to the extension of the idea or how the comprehension of the idea applies to the individuals of the extension.

A direct universal expresses the essence or nature of an object as it is found directly and immediately in the real order of objects existing all around us. The extension of the idea is not considered; the application of the universal to the individuals and the class is ignored.

There are different types of direct universals and various philosophers have designed different ways of organizing them into divisions. For our purposes, we will use a classification designed by Aristotle, who considered his categories to be the supreme and ultimate classes of predicates as found in our judgments and sentences. These predicates are direct universals and the categories are the supreme and ultimate classes of direct universals.

The categories determined by Aristotle are ten in number and it's easy to see, once each one is considered, why his system of categories appeals to common sense critically examined. These categories are very practical and very serviceable. Each one will be explained.

The first category is Substance. We've used this word before so it should be familiar. A substance is a being existing in and for itself. It doesn't need a subject in which to exist. A human being, a dog, a stone, a tree, a house are examples of substances. Each can exist in itself and for itself. If you ask the following question, the answer will express the substance: Who or what is this object?

The second category is Quantity. Quantity refers to the extension or number of an object. Weight and size are examples. "My dog stands two feet high." "This stone weighs twenty pounds." If you ask the following question, the answer will express the quantity: How much or how big?

The third category is Quality. Quality refers to a determining attribute in a thing. For example: strength, color, intelligence, temperature, and so on. "This dog is black." "That woman is really intelligent." "This stone is hard." If you ask the following question, the answer will express the quality: What sort of thing is it?

The fourth category is Relation. Relation is the reference or bearing of one thing to another. For example: maternity, equality, similarity. "She is a mother." "Sally is older." "Jane is a teacher." "Peter's hair is similar to John's hair." If you ask the following question, the answer will express a relation: To what or to whom does it refer?

The fifth category is Action. Action is the production of an effect in another. For example: drawing, making, driving, pounding, eating. "The dog is chewing a bone." "Sally is drawing a picture." "John is driving his father's truck." "Peter broke his leg." If you ask the following question, the answer will express action: What does it do to another?

The sixth category is Reaction. Reaction is the reception of an effect from another. Examples would include: being murdered, being lifted, being entrapped, being thrown, being heated. "The box is dropped." "John's fingers are burned." "Sally is hurled forward." "The boy is hit." If you ask the following question, the answer will express a reaction: What is done to it?

The seventh category is When. When refers to a situation in time. Today, sometime, a decade ago, and now are examples. "Peter went there last year." "Jane is going now." "The package will arrive at noon." If you ask the following question, the answer will express when: At what point of time?

The eighth category is Where. Where refers to a position in space. Examples of this are: on the table, in the box, below the top shelf, at school, up the river. "Sally is downtown." "The car is in the carport." "The book is on the desk." If you ask the following question, the answer will express where: Where is it?

The ninth category is Posture. Posture refers to disposition or attitude, immanent action expressed by an intransitive verb. Upright, standing, lying down, sideways, kiddy-corner are examples. "The house is leaning to the right." "Peter is running." "Sally is resting on the couch." If you ask the following question, the answer will express posture: In what attitude?

The tenth category is Habitus. Habitus is the outward modification of one substance by another, as expressed by the reflexive verb. Examples include: armed, clothed, being one's self, praising one's self. "John wears a blue coat." "The girl is disgusted with herself." "Jane has a yellow hat on her head." If you ask the following question, the answer will express habitus: How surrounded, how equipped, how conditioned?

 Always look to the primary meaning expressed in the idea in order to place an idea into its proper category. For example, "student" and "child" belong to the category of relation even though they are substances. "Student" is related to "teacher" and "child" is related to "parent." These reflect the primary meanings expressed in the ideas.

Many ideas can be placed in a category only indirectly or reductively. For example, parts go into the category to which the whole belongs. "Arm" is a part of "body" and belongs in the category of substance. "Branch" is a part of a "tree" or "plant" and belongs in the category of substance.