Epistemology: The Opinion on the Truth

Opinion is a state of the mind in which it decides for the truth of a judgment, but with fear of possibility of error. The best that the mind can attain with regard to the truth of its judgment is a certain amount of probability.

 

The reasons are good on both sides of the question; but the mind realizes that reasons for making the decision are weighty enough to justify adherence to one side of the question rather than to the other. The fear of error, however, hinders the mind from giving an unqualified assent to the judgment; there is still lack of certitude. Here is a case in point: Will the communists continue to rule for any great length of time in Russia? The fact that they have ruled many years is a good reason to assume that they will. But the fact that their rule is imposed by force and is fundamentally contrary to human nature, is apparently a better reason to suppose that it cannot last.

 

If I decide for the latter side of the question, I have an opinion that the communists will not continue to remain in power for any great length of time. Or, supposing all the evidence in a criminal case has been presented in court, and it is circumstantial and conflicting. I may weight this evidence and decide that the defendant is guilty, although I realize that there is good evidence against such a judgment: I have formed an opinion on the case.

 

Both in doubts and opinions there is lack of certitude. In doubts I can come to no decision, but in opinions I make a decision. in neither instance, though, can I overcome the fear of the possibility of error.

 

The mind is in a condition of hesitancy and uneasiness and remains in this attitude as long as a prudent fear of error lingers on. As soon as this fear of error is definitely overcome, hesitancy and uneasiness vanish and the min is at rest in a state of certitude.

Epistemology: The Attitudes towards Truth

Regarding many things man is certain that he possesses knowledge. He is equally certain that there are far more things of which he is totally ignorant. Again, he is conscious of the fact that he has made many errors in the past and that much of his present knowledge may be erroneous. He realizes also that he has no exhaustive and fully adequate knowledge of things, not even of himself. The consciousness of all this is reflected in his mental attitude toward the things he knows or thinks he know. These attitudes are doubt, opinion, and certitude.

 

What Doubt Is

 

Doubt is that state of the mind in which a suspended judgment ensues, due to the mind's inability to decide whether the judgment is true or false. If the mind can discover no reasons, or practically no reasons, which enable it to come to a decision regarding the truth or error of its judgment, then the doubt is negative. If it has discovered reasons, but if they are of practically equal weight for and against the truth of the judgment, thereby making a decisive judgment impossible, then the doubt is positive.

 

In both cases the result is the same: the fear of error cannot be overcome, and the judgment remains suspended. For example: Dark, heavy clouds are scurrying across the sky, and it looks as if it would rain. But the wind is high, and the clouds are traveling fast. Will it rain? The appearance of the weather indicates rain; but, the high winds may drive the clouds away. It might rain, but I fear it will not, and so I suspend my judgment: I doubt. Another case: Will the Army or the Navy win this year's football game?

 

Both have brilliant players; the one team is noted for its power, the other for its deceptive plays. The situation is such that the mind can come to no real decision: it doubts. And so there are innumerable instances where man cannot overcome his doubts.

Truth and Error

Knowledge has the quality of truth and error. The absence of knowledge in a being capable of possessing it is termed ignorance; thus, a man who does not know whether zinc is an element or a compound is in ignorance as to the nature of zinc. The absence of knowledge in a being incapable of possessing it is termed nescience; an animal, like a dog, does not and cannot know whether zinc is an element or a compound, and he is in a state of nescience regarding this fact.

 

It is only in the act of knowledge that we have truth and error. Truth and error enter into our knowledge, when this knowledge is expressed in judgments; that is when we affirm or deny something of something else. If what we affirm is really so as we affirm it to be, we have truth; otherwise we have error. For instance: I take a piece of metal in my hand, examine it, and state mentally, 'This is brass and not gold.' I both affirm and deny something here of the metal in my hand; I affirm it to be 'brass' and I deny it to be 'gold.' if this metal is really brass and not gold, then my double assertion (affirmation and denial) contains truth; but if it be really gold and not brass, then I am mistaken, and my double assertion contains error. As long as I merely look at the metal and form an idea of it, my knowledge is neither true nor false; but as soon as I apply an idea to the metal and mentally assert (affirm or deny) something about this metal in a judgment, then this judgment-knowledge automatically becomes true or false, depending upon whether or not my judgment and assertion corresponds to the reality-in-itself. Truth and error, therefore, are found in the judgment. This is mental or logical truth, and it consists in the conformity of the mind to the thing. Logical error is defined as a disconformity of the mind to the thing.

 

When we speak of truth as the 'conformity' of the mind to the thing, we do not mean that the 'nature' of the mind must conform to the 'nature' of the thing; we mean that the mind must conform to the thing cognitionally in its judgment.

 

There is, however, also truth in the things. We have, for example, a very definite notion of the metal called silver. This notion or idea of silver involves a number of subordinate ideas regarding the color, the specific gravity, the malleability, the hardness, the chemical constitution of silver; and this notion is a norm or standard to which a metal must conform in order to be designated silver. If the metal agrees with this standard, it is true silver, otherwise it is false silver.

 

The silver used in jewelry and that used in government coins is true silver; but German silver, being an alloy of copper, zinc and nickel is false silver because the real silver, being a chemical element of its own, contains none of these metals. When a stenographer copies a letter and the copy does not agree with the original, then the copy is false or erroneous; only if the copy agrees in every respect with the original is it considered a true copy. When, therefore, objects conform to a recognized mental norm or standard, they are said to possess 'truth of being' or 'ontological truth.' Ontological Truth is thus defined as the conformity of a thing to the mind. Reversely, ontological error consists in the disconformity of a thing to the mind.

 

From the explanation above, it will be clear how truth in general must be defined: it is the conformity between mind and thing. Error in general is the disconformity between mind and thing. Men universally distinguish between truth and error and consider them irreconcilable opposites. In epistemology must deal with logical truth and error, because its problem is concerned with the validity of human knowledge. The fundamental question is this: Can the mind transcend itself, reach to reality outside itself, conform to reality, and thereby acquire truth? There can, of course, be no question whether men think they can acquire a true knowledge of reality; all men have a natural, spontaneous, universal, and unshakable conviction that their mind knows many truths which give them a trustworthy insight into the nature and qualities of things. They are certain that their knowledge does conform to reality.

 

The fact of this conviction concerning the possession of logical truth is acknowledged by all; whether and how far this conviction is justified, will have to be determined by the critical examination of all the data and facts in the case. At present we are merely interested in acquiring a clear conception of the ideas and terms involved. For that purpose it was necessary to specify the exact meaning of truth and error in so far as they may be found in human knowledge.

 

What You Should Know About Knowledge

When we speak of the 'problem of knowledge,' it is not a question whether man possesses 'knowledge.' That is a fact which no one denies. So we must begin with the idea of 'knowledge.'

 

Knowledge is a primary fact of human life and experience. Everyone understands what it means 'to know,' 'to have knowledge.' But when we attempt to explain and analyze this idea, we immediately encounter difficulties. Just because it is a primary fact of experience, the idea of 'knowledge' eludes every effort at an exact definition. We can point out certain characteristics of 'knowledge' and adduce definite instances of 'knowledge,' but we cannot really define it. 'To know' is on a par with 'to see,' 'to taste,' 'to touch,' 'to imagine,' 'to will.' Man is simply conscious of these states of his being and gives them a name; and thus he arrives at the idea and the term. It is useless to try to explain to a man born blind what 'color' or even 'seeing' is; just as it is useless to explain to a man born deaf what 'sound' or 'hearing' is.

 

We can place a man in a certain position and say to him; 'Open your eyes and tell me what you see across the park.' 'I see the Court House.' 'You are sure of it?' 'Yes, I am sure of it.' 'Then you know that the Court House is there.' Or we can say to him: 'Listen; do you recognize the melody?' 'It is the Funeral March of Chopin.' 'Good; then you know the melody.' Again, we may notice that he looks ill and ask: 'What is the matter?' 'I have a headache.' 'Well, then you know what pain feels like.' And so on. It is the experience of this sort which constitutes 'knowing' and 'knowledge.'

 

Now, there are three elements which enter into knowledge: the knowing subject, the known object, and the mental act of knowing (cognition). The subject is the one who knows; the object is the thing that is known; and cognition or knowing is the mental act which makes this object known to the subject.

 

The subject, the knower, is man as we notice it in the phrase: 'This man knows his business.' Taken individually, it is the Ego, the 'I myself,' who am the knowing subject, for we say: 'I know this house, this game, this boy.' All our activities are referred to the Ego as the subject. We become aware of this, if we reflect upon the following expressions: 'I walked a mile; I saw an accident occur; I feel a pain in my side; I taste garlic in my food; I smell a pleasant odor in the kitchen; I thought about the depression; I know about the plans of my friend; I was conscious of the act.' Knowledge, then, as a mental activity, belongs to the Ego, the self, as the 'subject' who knows. And it is in this sense that the idea of 'subject' must be taken in the epistemological problem of knowledge, because that is the spontaneous conviction involved in our way of thinking.

 

The object of knowledge is anything and everything that is, or becomes, or can be, known by man. According to man's spontaneous conviction the objects of his knowledge comprise his own self, various conscious states of his self, and also realities-other-than-self, is a plain fact which he manifests in numberless judgments of everyday life: 'The sun is shining; the wind is blowing; the meal is good; this building is tall; some roses are red.' In all such judgments the ordinary man refers his knowledge to some object, and he is sure that the object is as real as the subject. Whether his common sense view that such 'realities-other-than-self' belong to an exterior world with an independent existence of their own outside man's mind, is precisely one of the problems to be solved. But that every act of knowledge must be 'knowledge of something' and therefore refer to some object is perfectly clear and is disputed by nobody.

 

The object becomes known to the subject by the act of knowing. This act, of course, takes place in the subject or knower. It is a unitive act, in as much as it brings the object and the subject into contact with each other, thereby rendering the object 'present to' the subject and making the subject 'aware' of this presence of the object. Before being known, the object is merely an 'object-in-itself'; but through and in the act of knowing it now becomes an 'object-to-the-mind.' and it is by becoming an object-to-the-mind that a thing becomes 'known.' Somehow or other, then, an external physical object (if there be such) must become untied to the mind of the subject by means of the cognitional act and be presented to the Ego as an 'object-to-the-mind,' in order that it can become 'known' by the subject; in other words, the object must become intra-mental and intra-subjective, before it can be known. A simple example may make this clearer. I see a burning house and 'know' it to be burning. How do I get to know this fact? The house is perhaps a hundred yards from where I stand.

 

Surely my mind does not leave my person, cross the intervening space and physically contact the flaming building nor does the burning house leave its foundation, travel over to me, enter my mind and then actually burn inside my person. Nevertheless, the burning house and my mind must become united in some way, or I could not know that the house is burning. Since the house has no physical presence inside my mind, it must have a cognitional presence there by means of sense-perception and thought. An object, then, in order to become known by the subject must acquire an intra-mental and intra-subjective presence or existence, must become an object-to-the-mind, must have a mental objectivity, must become an ideal being.

 

The very act of knowledge demands this sort of presence of the object in the subject; otherwise no union would take place between subject and object, and knowledge would not be possible. The question, of course, arises: Has this object (for instance, the burning house mentioned earlier) a real, extra-mental existence of its own outside the self and the mind, independent of the cognitional existence which it has in the mind in the act of knowledge? The ordinary man is convinced that it has an objectively real existence outside the mind; idealists on the contrary, assert that we can know nothing but what takes place subjectively in our mind, and that we therefore have no right to affirm the existence of any thing-other-than-self. And so we again are face to face with the fundamental problem of knowledge. Whatever the solution, this much is clear and recognized by all: an object, in order to be known must be cognitionally present in the subject in the act of knowing.

 

The subject, the object, and the act of knowing are thus the essential elements necessary for knowledge. Whatever pertains to, or proceeds from, the subject is subjective; and whatever pertains to, or proceeds from, the object is objective. The state or condition of being subjective or being objective is then styled subjectivity or objectivity. And anything that pertains to, or proceeds from, the act of knowing or cognition is termed cognitional or intentional. Knowledge will thus be either subjective or objective; viewed from the standpoint of the subject who knows, it is subjective; and considered as referring to the object which is known, it is objective. So much for knowledge as it exists in the knower.

Epistemology: The Science of Knowledge

Epistemology (from the Greek word episteme which means knowledge and logos which means doctrine) is the science of the validity, or truth-value of human knowledge. It is a 'science'; that is, it is a definite body of truths, derived from reasoned demonstrations of causes and reduced to a system. It is the 'science of human knowledge.'

 

Here we have the general subject-matter of epistemology: it is not the purpose of this department of philosophy to investigate the nature of the human mind and its faculties, but that phase of the mind's activity which we designate by the term 'knowledge.' It is the 'science of the validity, or truth-value, of human knowledge.' This is the special or formal subject-matter of epistemology, distinguishing it from the other departments of philosophy and from every other science. The sciences are concerned with knowledge, because they increase our knowledge of things; but they do not treat of knowledge from the standpoint of its 'validity' or 'truth-value.' It is the purpose of epistemology to submit our knowledge to a critical examination and investigate the rational grounds on which it rests, so as to discover whether and why we are justified in having the spontaneous conviction that our knowledge is valid and true in its claim to be a faithful interpretation of reality.

 

The definition shows us in what way epistemology differs from logic and psychology--two sciences closely related to epistemology. Logic is the science of 'correct' thinking. It gives us the laws and methods which we must follow, if we desire to avoid error and inconsistency in our mental acts; it is concerned chiefly with the proper arrangements of our ideas, judgments, and argumentations, so that a legitimate conclusion can be drawn from given truths. Psychology is the science of the soul in its nature and activities. This embraces everything pertaining to the soul of man, including knowledge. But so far as knowledge is concerned, psychology endeavors to lay bare its origin and nature, rather than its validity or truth-value.

 

Epistemology, as a special science, leaves aside the formal correctness, the origin and nature of the act of knowledge, and seeks to establish its validity and truth in so far as it is supposed to be knowledge of things. For that is a peculiarity of human knowledge: we are convinced that it actually makes us acquainted with reality and gives us a true conception of reality as it is in itself. This conviction, however, cannot simply be assumed; it must be established beyond reasonable doubt, otherwise philosophy and science will be without secure foundation. It is plain that, because of the close relationship existing between logic, psychology, and epistemology, it must at times reach over into the fields of the other two sciences, because an understanding of the laws and nature of thinking is necessary to form a proper judgment about he truth-claim of knowledge. As such, then, epistemology differs from logic and psychology.

 

The term 'epistemology' is of comparatively recent origin. Formerly it often went under the names of 'applied logic,' 'material logic,' 'critical logic,' or 'noetics.' Now it is customary to separate this part of philosophy from the logic and treat it as a special science. The reason for this procedure lies in the fact that the problem of knowledge has become the major philosophical problem of the past three centuries. This does not mean that the validity of human knowledge had received little attention in the preceding ages. It had been discussed since the very beginnings of philosophy in ancient Greece; but it has never held the predominant position in the minds of thinkers that it occupies today. Today it is the problem of philosophy. The importance of the problem will become apparent as we advance in our investigation.

 

Epistemology is sometimes called criteriology. But there is a distinction between the two. Criteriology, as the term implies, is the science of the criteria of truth. The criterion of truth is the norm or test or standard which enables us to distinguish truth from error. Any theory of knowledge, to be complete, must treat of the criterion of truth; but there are many other questions involved in the validity of knowledge. Criteriology, therefore, is only a part of epistemology and as such does not cover the entire field usually assigned to what is known as 'the problem of knowledge.' Epistemology, on the other hand, considers this wider and more fundamental problem in all its phases.

 

Criteriology asks the question: 

·         What distinguishes truth from error? 

Epistemology asks the question: 

·         Is our knowledge of things objectively valid and true? 

Plainly, we can inquire into the existence and nature of the criterion of truth only after we have established the prior fact of the validity, or truth-value, or our knowledge in general.

 

This then, is the problem which confronts us: To investigate human knowledge and seek to determine the rational grounds upon which the validity of our spontaneous convictions are based. If we can establish this validity, these convictions will be critically and philosophically justifies; if we cannot, our common and scientific knowledge must be considered to the nothing better than conjectures which may give us more or less probability but never the security of philosophic certitude.

 

The Validity of Spontaneous Convictions

Taking the example stated in the previous article, The Problem of Knowledge, it is clear that the philosopher has a right to question the validity of the spontaneous convictions of man and to investigate their claim to truth and certainty. Just as it is necessary to examine the foundations of the ordinary man's views on nature and physical phenomena, so philosophy needs to lay bare the ultimate grounds and reasons of man's knowledge and spontaneous convictions, in order to see whether why will survive the test of critical examination in the light of reason. If they survive, then they will be so much the firmer, since they will rest upon a scientific foundation; if they are disproved, they must be discarded as obsolete and irrational, the same as many naive and unscientific ideas of a bygone age regarding physical phenomena and their causes.

 

Man is a part of nature, and his knowledge is also a phenomenon of nature; as such it should be analyzed and examined in its origin, development, and truth-value, to see whether it really gives us a true interpretation of the world around us and can lead us to a well-reasoned certitude. For that is the purpose and function of philosophy: to investigate and demonstrated the ultimate grounds and reasons of things.

 

To the ordinary man nothing seems simpler than his knowledge; but to the philosopher the problem of knowledge is by no means so simple as it seems. The speculative mind of the philosopher discovers a multitude of knotty questions which puzzle him sorely and for which he would fain find a solution. He is not at all sure that the spontaneous convictions and beliers of the ordinary man deserve the credence accorded them. Science has disillusioned man regarding many of his century-old notions and convictions; and science itself has gone through many battles of conflicting opinions and hypotheses, reversing its conclusions in more than one instance. It is, therefore, no idle question to ask:

 

·         What can we know?

·         How far can the mind of man reach?

·         Is valid knowledge really attainable?

·         Is truth objective?

·         Can we be absolutely certain about anything?

 

The inductive sciences, such as physics, chemistry, astronomy, geology, biology, physiology, and anthropology, are all based on ideas, principles, and laws derived from the objects and operations of nature, and the knowledge acquired in and through these sciences is almost entirely the result of sense-experience and experiment. Even the deductive sciences like arithmetic, algebra, geometry, trigonometry and calculus are based on the ideas of quantity derived from space and number in material nature.

 

The science, therefore, depend upon the validity of sense-perceptions and intellectual concepts to guarantee the foundations upon which they rest. Science, after all, is a body of universally applicable truths, formulated by the intellect as the result and expression of innumerable inductions and deductions. The value of sciences will, therefore, necessarily remain in doubt until philosophy has given a satisfactory account of truth, certainty, and the ultimate validity of human knowledge in general. Thus it is imperative to vindicate the validity of knowledge both from the empirical and intellectual side, because science is the combination of both these phases.

The Problem of Knowledge

It is this urge for knowledge which accounts for the rise and development of the sciences. Not satisfied with the superficial appearance of thins, as the ordinary man sees and knows them, chemistry searches for the component elements of bodies, their activities and energies, their nature and qualities, their workings and the laws of their combinations.

 

Gases (e.g. air), fluids (e.g. water) and solids (e.g. stones) are now understood to be, not bodies consisting of homogeneous material, but chemical compounds of very divergent elements united in definite quantities according to definite proportions under definite laws through the expenditure of definite proportions under definite laws through the expenditure of definite amounts of energy. Not satisfied with the ordinary explanations of physical happenings in nature, physics attempts to discover their underlying causes and to chart their course of action from start to finish.

 

Not satisfied with the common view that life in all its phases and functions is an inexplicable mystery, physiology and biology and kindred sciences have probed deeply into the hidden recesses of living organs and tissues and have wrested from them many secrets hitherto unsuspected.

 

Many things concerning life have advanced into a clearer stage of scientific knowledge: among others, cell organization and function, the origin and growth of organisms, bacterial infection with corresponding medical treatment and international disease control, aseptic surgery, the proper distribution of nutritive values in foods. Similar progress has been made in the other sciences, due to the urge for deeper knowledge inherent in the human mind.

 

All of this shows that scientific investigation of such problems is not a futile occupation. In many instances age-old spontaneous convictions have been confirmed by science, and in other instances they have been disproved. Many supposedly certain truths have had to be discarded, to give place to more reliable information. Thus, to mention a case in point, the Ptolemaic geocentric system, in which the earth was considered to be at the center of the universe with the sun and moon and stars revolving around it, has been proved by science to be false and has had to make room for the Copernican heliocentric system, in which the earth was relegated to the secondary position of one among many planets revolving around the sun.

 

This one instance has an important bearing on the problem of spontaneous conviction and knowledge. From the standpoint of human experience, nothing appears plainer than that the sun revolves around the earth. Yet we now know that the moon does, and the sun does not; but to all appearances both sun and moon travel through the sky in the same way. Similarly, due to the atmospheric refraction of light, both sun and moon are seen in the east before they are above the horizon, and in the west they are seen after they are below the horizon. Both are seen as deep-red in color when they rise and set; and both balloon out to a number of times their normal size, with bulging sides and flattened upper and lower poles; they shrink as they ride to the zenith and grow larger as they descend.

 

Actually, however, the sun and the moon do not increase and decrease in bulk, and at no time are they red in color. Again, the sun never actually grows warmer in the course of the day, nor is it any hotter in summer than in winter, nor does it change its position in the sky during the seasons of the year: its position in the firmament and its temperature are always the same. But the testimony of our senses seems perfectly clear regarding these changes, and mankind for thousands of years has had a firm, spontaneous conviction of the truth of this testimony. And even though science has furnished indubitable proof that our spontaneous conviction is wrong, our sense-experience still testifies to the same phenomena; but the fact remains that spontaneous convictions can be radically wrong, even when based on apparently irreproachable evidence of the sense. This is borne out by many instances besides the case mentioned above.

 

Spontaneous Convictions

Facts of everyday experience, such as those mentioned in the previous article, Facts and Knowledge, could be multiplied indefinitely. The ordinary man has a spontaneous and unshakable conviction that they are genuinely true. No amount of argument could convince him that his knowledge is not valid. He may not be very clear in his own mind about the scientific and philosophic grounds and proofs for this conviction, but of the reality of the world and of the truth of the facts he entertains not the slightest doubt. His common sense tells him that he is right. Every moment of his life, from the cradle to the grave, confirms his convictions that the world outside and around him is as he experiences it to be and that his knowledge of it is a correct insight into its reality. The whole substance of these convictions can be summed up in this: the world is objectively real and man has a genuine knowledge of it as it is.

 

They are not forced convictions, accepted by the mind against its better judgment; rather, they are spontaneous for the very reason that they are the natural and obvious interpretations of the things and happenings in which man lives, and all together they form a system of knowledge which agrees with the demands of his rational nature. Man lives with and by and in these convictions, and these convictions are found by daily experience to be in accord with the facts as he knows them. Hence, he never questions their truth and validity; to him they are self-understood and self-demonstrative, and he feels perfectly safe in their possession.

 

This, of course, is strong presumptive evidence in their favor. If man's whole life can be regulated by them, in a practical as well as in a rational manner, then it is a prima facie proof that he is right in his assumptions. It would, then, seem superfluous for the scientist and philosopher to investigate the grounds and reasons of these spontaneous convictions. But such is not the nature of the human mind in its insatiable desire for deeper and more extensive knowledge. Man's mind simply cannot rest satisfied with the obvious and transparent explanation of facts. The urge for knowledge prompts him to investigate the foundations, the ultimate grounds and reasons, the 'how' and 'why' of these spontaneous convictions.

Facts and Knowledge

Many things are directly mentioned as existing, and a spontaneous conviction is expressed regarding 'facts' and 'knowledge' in the self-communing quoted in the previous article, Statement of the Problem.

 

He 'watches the world go by.' so he is sure that there is a real world of substance, an existing universe of tremendous magnitude, consisting of earth and sun and stars. He may have no conception of the exact dimensions of this universe, or of the distance and volume and nature of the stars; but he is sure that they are really there and that he does not merely imagine them.

 

He speaks of space and space-relations: for people are walking 'along the street,' there is a 'square opposite,' the sun is 'sinking in the west'; he notices a 'here' and 'there,' an 'outside' and 'inside.'

 

The person also mentions time and time-relations: 'yesterday,' 'tonight,' 'tomorrow,' 'soon'; and the elements of succession in time are designated by the phrase 'every minute.'

 

Mathematical quantities are affirmed: 'square,' 'larger,' 'flatter.' And also numerical quantities appear: 'people,' 'stars,' 'tree.' He notices the relation of part to whole in the 'branch' that is broken off the 'tree.'

 

There are qualities, like 'blue,' 'strong,' 'cold'; actions like 'walking,' 'sinking,' 'broke off'; reactions like 'caught a cold,' the branch 'broken' by the wind; posture like 'sitting in comfort'; habitus like 'being clothed with a topcoat.'

 

Facts of sense-experience are enumerated: he 'sees' the things about him on the earth and in the sky; he 'hears' people chatting; he 'tastes' his pipe; he 'feels' sick; he is 'conscious' of his body. And so, too, facts of intellectual experience are noted: consciousness of the Ego or 'self,' 'thoughts,' 'knowledge,' 'soul'; states of mind like 'belief,' 'errors'; states of will like 'I must,' 'I ought not.'

 

He is aware of the great distinction between his self and things-other-than-his-self; between mind and matter; between living and inanimate things; between the subjective and objective; between the ideal and the real; between substantial and accidental being; between appearance and reality; between knowledge and opinion; between truth and error; between certainty and probability.

 

And many other things are contained in the data of his musings by implication. He is convinced that his senses, by and large, give him a true picture of the world about him and that he can trust them in their function of bringing the world into contact with his mind by means of the sense-organs of his body. He is also convinced that his intellect, through judgment and thought, can acquire a knowledge of the world and of himself which is true and valid and certain. He realizes that his mind can make 'errors' and that appearances may deceive (as when the sun 'appears' flatter, bigger, and redder, and when the sky 'seems' to turn into fire and gold); but he also realizes that his mind can detect errors and correct deceiving impressions, finally arriving at truth. Furthermore, he knows that truth is objective, that his mind does not fabricate truth but merely discovers it, and that his mind will posses truth only when it agrees in its judgments with the things as they are in themselves.

Statement of the Problem

Knowledge is at once the simplest and the profoundest of human experiences.

 

Nothing seems more plain to the ordinary man, and more beyond the possibility of any doubt, than the everyday facts if his knowledge. He is utterly convinced of the truth and certainty of the happenings in and around him. It never enters his mind to question the validity of his convictions concerning the knowledge of his experience. We may imagine him sitting in his lounging chair before a window and communing with his thoughts:

 

"It is certainly pleasant to sit here in comfort and watch the world go by. People are hurrying home from their business, chatting noisily with one another as they walk along the street. The sun appears flatter, larger, and redder every minute, as it slowly sinks in the west, and little by little the blue of the sky seems to turn into fire and gold. Soon the darkness will be here, and I shall see the distant stars. I did not think the wind was so very strong, but I see that it broke a branch from the tree in the square opposite. It is much colder than it was yesterday; I believe that will cause a frost tonight. The air is very raw outside. I ought not to have gone without a topcoat this morning. I believe I have caught a cold; I felt miserable all afternoon, I had a headache, the old pipe didn’t taste, and my mind was so foggy that I couldn't control my thoughts properly, and I made a number of errors. I am not myself now. I must see my physician tomorrow; he knows my body almost as well as I know my soul."

 

All this seems so simple and matter-of-fact, and the knowledge contained in these statements seems so obvious and transparent, that we should scarcely consider it worthy of second thought. Much less should we think that philosophers could discover any deep and mysterious problems hidden in the desultory musings of an old gentleman seeking comfort in his easy-chair. Such, however, is precisely the case.