STUDY GUIDE TO RUSSELL'S PROBLEMS OF PHILOSOPHY by James Fieser Bertrand Russell's Problems of Philosophy is an introduction to a branch of philosophy known as epistemology. Epistemology is the study of knowledge, and particularly how knowledge is attained. The opening sentence of the book expresses this: "Is there any knowledge in the world which is so certain that no reasonable man could doubt it?" Russell's answer is no. He does not, however, recommend extreme skepticism. We should still investigate these issues so to "substitute articulate hesitation for inarticulate certainty." The goal of philosophy, then, is not to establish definite answers, since as a rule no definite answers can be known. Instead, the purpose of philosophy is to ask questions which "enlarge our conception of what is possible, enrich our intellectual imagination and diminish the dogmatic assurance which closes the mind against speculation" (p. 161). In showing that absolute knowledge cannot be attained, Russell discusses the two classic types of knowledge: a posteriori and a priori. A posteriori knowledge is knowledge about the physical world, or knowledge which is attained by the senses. A priori knowledge, on the other hand, is, in Russell's words, knowledge of general principles of inference (including laws of induction, mathematics, identity, and contradiction). Accordingly, Chapters One through Five deal with a posteriori knowledge, and Chapters Six through Ten deal with a priori knowledge. The remaining five Chapters of the book involve epistemological concepts which apply to both a posteriori and a priori knowledge. CHAPTER ONE: APPEARANCE AND REALITY Chapter One is an introduction to the first five Chapters (all of which deal with the problem of a posteriori knowledge). After asking whether there is any knowledge in the world which is so certain that no reasonable man could doubt it, Russell suggests that we begin with our present experiences (that is, with a posteriori knowledge). He focuses specifically on one object of experience: a table. By examining the table, the goal is to distinguish those qualities of the table which really belong to it, from those qualities which merely appear to belong to it. (1) What aspect of the table is the painter interested in, and what aspect is the philosopher interested in (T-M 9)? (2) List the qualities of the table which only appear to belong to it (M 9- M 11). (3) What does he conclude about the real table (B 11)? (4) What are the two questions which can be asked about the table (B 11)? Taking the issue of a posteriori knowledge further, Russell defines some key epistemological notions. (5) What are sense data (T 12)? (6) What is matter (B 12)? Russell, like Descartes subscribes to what is called the causal theory of perception. On this theory, perceptions are caused by physical objects. For Russell, though, there is a link between physical objects and perceptions: objects > sense data > perceptions (7) Revised, what are the two questions we want to ask about a posteriori knowledge (B 12)? (8) Through the character of Philonous in his Dialogues, why does Berkeley deny matter (T 13)? (9) How does Berkeley answer the two main questions about knowledge of matter (T-M 15)? (10) What are some of the ways people have conjectured about the nature of matter (B 16)? CHAPTER TWO: THE EXISTENCE OF MATTER In Chapter One, Russell stated the problem of matter in two questions: (1) is there any such thing as matter? (2) if so, what is its nature? In this Chapter, he answers the first of these two questions. He begins by noting the importance of knowing whether there is any such thing as matter. If we cannot be sure that matter exists, then we cannot be sure of the independent existence of other people's bodies, and much less can we be sure of the existence of other people's minds (i.e. the existence of intelligence apart from one's own). In his quest for knowledge about whether matter exists, Russell begins by reviewing Descartes' systematic doubt, culminating in Descartes' assertion, "I think, therefore I am" (cogito ergo sum). (11) Why, according to Russell, is Descartes' assertion not about the real self (T-M 19)? (12) What, for Russell, is the only thing that we can be certain about when we assert "I think, therefore I am" (B 19)? Granted, we know that there are sense data. The issue now (in the quest for whether matter exists) is whether these sense data are produced by matter. Common sense would tell us that there is matter beyond the perceived sense data. This common sense inclination is evident in that we desire that there be publicly neutral objects. That is, we want the same object for different people. (13) What is the philosophical justification for believing in publicly neutral objects (M 21)? (14) Why does this reasoning fail to show that matter exists beyond an individual person's sense data (B 12)? Russell concludes, then, that the question of the existence of matter can only be answered by appealing to one's own perceptions or experiences-not by appealing to the experiences of a community of people (or other minds). Even then, appealing to one's own experiences will never produce certainty about matter's existence. The reason is that the philosophical position of solipsism can never be refuted. Solipsism is the position that only the individual who perceives things actually exists. Everything else is just an illusion, hallucination, or an aspect of consciousness, ultimately produced by the individual's own mind. No argumentation can strictly disprove solipsism. Consequently, according to Russell, no argument produced from one's own experience can strictly or absolutely prove that matter exists. The only route of argumentation left is to show that an hypothesis claiming that matter exists, is better than (i.e. more complete, or more simple than) an hypothesis which denies that matter exists. Russell shows this with three arguments. (15) How does Russell's example of a moving cat show that the hypothesis maintaining that matter exists is more simple that the hypothesis maintaining that matter does not exist (T 23)? (16) How is this shown in his example of a hungry cat (M 23)? (17) How is this shown in his example of hearing humans speak (B 23-T 24)? Since belief in the existence of matter is (a) an instinctive belief, and (b) simplifies and systematizes our account of our experiences, Russell concludes that we should accept the hypothesis that matter exists. Since instinctive belief is an important reason why we believe that matter exists (even though we cannot absolutely prove that is does), Russell concludes Chapter Two by making some comments about instinctive belief. As Hume argued, humans have a number of instinctive beliefs, some of which deserve higher priority than others. For instance, instincts which have us believe in causality, or external objects have a higher priority than those which incline us to be superstitious. According to both Hume and Russell, one of the jobs of philosophy is to rank order our instinctive beliefs in terms of priority and reliability. For Russell, this is done by noting which instinctive beliefs have a higher possibility of yielding true judgments, in contrast to those which more often lead us into error. CHAPTER THREE: THE NATURE OF MATTER Being confident (although not certain) that matter exists, Russell turns to the question of the nature of matter. He begins with a very general scientific view that matter ought to be reduced to wave motions in either aether or gross matter. Aether, in this sense, is defined as an all pervading, infinitely elastic, massless medium. Gross matter, by contrast, is roughly that which has weight. What is important about matter to the scientist, though, is only its wave producing qualities, since only these qualities can be detected by instruments, or perceived by humans. Taking this scientific view as a point of departure, Russell continues by discussing the nature of matter negatively, that is, by describing those features which are not part of matter. For example, light itself is not part of the nature of a light bulb: a light bulb only produces waves (or photons). The perception of light, on the other hand, depends upon properly functioning eyes which receive the sense data produced by the waves. (18) What other commonly perceived qualities are not part matter (or not really found in the outer world; M29)? Much of Russell's positive description of matter is given through his analysis of space, since (a) we believe that matter exists in space, and, (b) matter itself takes up space. (19) What is the difference between real and apparent space (B 29-T 30)? (20) What is the relation between real and apparent space (T 31)? (21) How does Russell's eclipse example illustrate the limitations of what we can know about lines in real space, when being inferred from lines in apparent space (B 31)? (22) In contrast to the relation existing between real and apparent space, what is the relation between real (or public) time, and apparent (or private) time (B 32)? (23) How does Russell's lightning example illustrate the limitations of what we can infer about events in real time from our perception of events in private time (M 33)? (24) What is the relation between real color and apparent color (M 24)? (25) Russell concludes by refuting a position known as modified realism. Realism is the position that we perceive objects as they are. Modified realism, by contrast, is the view that although real objects cannot be exactly like our perceptions, they are, more or less, as they are perceived. What is his criticism of modified realism (M 34)? Russell concludes that we may know some very general things about the nature of matter, based on our perceptions. For example, we can say that matter takes up space, that it exists in time, and that there is something about it which causes us to have perceptions of color. However, we cannot know what real space, real time, or real color producing qualities are actually like. What remains for Russell to show is that one can never be justified in claiming to know the real nature of matter. Idealists, as we have seen, believe that the real nature of our perceptual causes is mind. Consequently, Russell turns in the next chapter to a refutation of idealism. CHAPTER FOUR: IDEALISM Idealism is the view that whatever exists or can be known to exist, must be in some sense mental. Russell begins noting some common sense refutations against idealism. One of these stems from our belief that matter existed long before there were any minds, hence it is hard to think of matter as a mere product of mental activity. (26) What is wrong with common sense refutations of idealism (T 38)? Berkeley, the most convincing of the idealists, presented an argument for idealism as follows: (1) Sense data (or perceptions) do not exist independent of us, and, therefore, must exist only in the mind as ideas. (2) Sense data are the only things we can know. (3) Therefore, everything we can know must exist only in the mind as ideas. This argument is summed up in the Latin phrase, "esse is percipi," or, "to be is to be perceived." Faced with the problem that things continue to exists when no human is there to perceive it, he concluded that God must always be perceiving things so they continue to exist. Russell's first criticism of idealism is based on Berkeley's misuse of the term idea. For Berkeley, an idea is any mental event, including a sense perception or a memory of a sense perception. According to Russell, Berkeley's use of this term is incorrect since it confuses two distinct concepts: (1) the object which is apprehended, and (2) the act of apprehending. In other words, the idealist correctly notes that all acts of apprehension are mental events (e.g. the act of apprehending a tree, based on one's perceptions). But the idealist continues by assuming that if all acts of apprehension are mental, then the object which is apprehended must be mental too. Confusing the object of apprehension with the act of apprehension is, for Russell, the idealist's fallacy. Having dismissed Berkeley's argument for idealism, Russell briefly entertains a final argument in favor of idealism: (1) If matter can be known to exist, then we must be acquainted with matter. (2) If matter is relevant to our experience, then we must be acquainted with matter. (3) It is not the case that we are acquainted with matter. (4) Therefore, matter is neither relevant to our experience, nor known to exist. (5) Things which are real must be of practical importance. (6) Therefore, matter is not real. (27) How does Russell refute premise five in the idealist's argument above (B 43-T 44)? Russell also attacks premise one in the above argument by making a distinction between (a) knowledge attained when we judge something to be either true or false, and (b) knowledge attained when we are immediately acquainted with something (such as knowledge of sense data). The idealist is correct if premise one is interpreted to mean that knowledge by direct acquaintance requires direct acquaintance. This is obviously true. What is not obviously true is when the idealist interprets premise one to mean that knowledge of truth and falsehood requires direct acquaintance. (28) How does Russell's example of the Emperor of China refute this second interpretation of premise one above (B 44)? Russell concludes his criticism of this argument by noting that the idealist unjustifiably limits our realm of knowledge to those things with which we are directly acquainted. Granted, knowledge by acquaintance is an important aspect of knowledge, such as when we claim to know that the table directly before us is brown. Such knowledge by direct acquaintance does not, however, exhaust all the ways which we may judge something to be true or false. We also attain knowledge of the world by description. Here, given a description of some thing, such as "the current president of the United States," we can have knowledge about whether this thing exists, without direct acquaintance with the current president. That is, we can have knowledge of his existence by being reading about him in the paper. This important distinction between knowledge by acquaintance and knowledge by description is the subject of the next chapter. CHAPTER FIVE: KNOWLEDGE BY ACQUAINTANCE AND DESCRIPTION For Russell, saying "I know X" may means one of two things. First, it may mean that I know X by being directly acquainted with X (knowledge by acquaintance). Or, it may mean that I know X by having only indirect knowledge of some object or fact, for example, by reading a history book (knowledge by description). Russell's basic distinction here is obvious. If I say that "I know that Michael J. Fox is short," I could know this by either directly seeing Michael J. Fox, or by reading a tabloid article which reveals his short stature. Russell makes an issue of this obvious distinction since epistemologists before him have ignored it and focused only on knowledge by acquaintance. (29) What does Russell mean by "acquaintance" (B 46)? (30) What things about the table can we know by acquaintance (T 47)? (31) What things can we not know about the table by acquaintance (M 47)? Russell argues that we can have direct acquaintance of only a few types of things. One type is sense data, since these are things which are directly presented to our senses. Another thing is memory. Here our ideas of past events are perceived directly before our mind's eye. We are also directly acquainted with our bodily feelings, such as hunger, and our emotions, such as anger. Additionally, we are directly acquainted with our awareness of our hunger, or, more generally, with our own introspection. (32) What, for Russell, is one of the differences between humans and animals (B 49)? Russell next raises the question of whether we are directly acquainted with our self. Hume argued that we have no direct experience of our self: "For my part, when I enter most intimately into what I call myself, I always stumble on some particular perception or other, of heat or cold, light or shade, love or hatred, pain or pleasure. I never can catch myself at any time without a perception, and never can observe anything but the perception." (Treatise p. 252) (33) What is one reason why we might believe that we are directly acquainted with the self (T 51)? (34) What does Russell finally conclude about knowledge of the self (M 51)? For Russell, we can be directly acquainted with sense data, memory, bodily sensations, emotions, introspection, and possibly the self. Along with these he adds that we may be directly acquainted with universals (but more of this later). He then turns to an examination of knowledge by description, that is, knowledge we have by reading or hearing about something, but not directly perceiving it. The list of things about which we have knowledge by description is endless. Anything we know by reading in print, seeing on T.V. or hearing on the radio is knowledge by description. So, Russell's interest in knowledge by description is not to list the things about which we can have this sort of knowledge. Instead, he is interested in explaining what linguistically takes place when we say "I know X" by description. He begins his investigation by distinguishing between ambiguous and definite descriptions. (35) What is the difference between ambiguous and definite descriptions (M 52)? Russell focuses entirely on definite descriptions. To understand his rather complicated linguistic account of knowledge by definite description, we must first distinguish between two sorts of descriptive knowledge claims. The first sort is an existence claim, such as, "I know he (Michael J. Fox) is the kid who plays Alex Keaton on Family Ties." Here the claim of knowledge is only about the existence of some person (e.g. the guy who plays Alex Keaton of Family Ties). The second sort of knowledge claim is a detailed knowledge claim, such as, "I know Michael J. Fox is short." Here the claim of knowledge is about a quality (e.g. shortness) which a certain person has. Russell first examines existence claims. (36) With an existence claim, when we say an object is known by description, what do we mean (T 53)? When we have knowledge of an object's existence by description, Russell argues that the description of the object in question (i.e. "the so-and so") must be unique. For example, when we say that "I know he is the guy who plays Alex Keaton on Family Ties," the description here (i.e. the guy who plays Alex Keaton on Family Ties) applies to only one person: Michael J. Fox. In short, when I have knowledge by description of the existence of some object or person, this knowledge is based on a uniquely definite description of that object or person. Unfortunately, the issue gets more complicated. When I say "he is the so-and-so," I am really using two definite descriptions: one represented by the "so-and-so" (which was just discussed) and another represented by the word "he." In other words, proper names and pronouns are also disguised definite descriptions. For example, suppose I look at a picture in People magazine and say, "he is the kid who plays Alex Keaton in Family Ties." The word "he" here stands for a definite description such as "the guy who posed for this particular photo," since only one, unique person posed for that picture. Written out formally, then, when I look at that photo, and say "he is the so-and-so," my utterance really means, "I know that the kid who posed for this photo is the kid who plays Alex Keaton on Family Ties." Thus, knowledge of an object's existence by description involves two definite descriptions. Remember, Russell is only giving a linguistic account of what happens when we know of an object's existence by description. Detailed knowledge by description is another story. For example, if I look at that same picture in People magazine and say, "I know he is short," once again, "he" here is a definite description. In this case, "he" could mean "the guy who posed for this photo," or "the star of Back to the Future." The actual description intended will depend on what we are thinking about at the time when we see the photo. The fact remains, however, that Russell believes that the pronoun "he" must be represented by some definite description, if we are to meaningfully say, "I know that he is short." It is important to note here that the predicate "is short" is not a definite description of Michael J. Fox. Millions of people are short. What is meant is only that the person who is in the photo before us (a definite description of Michael J. Fox) has the quality of being short. Thus, with detailed knowledge claims by definite description, only one definite description is present (along with a predicate describing a quality). This is in contrast to existence claims by description where two definite descriptions are present. Russell's analysis of definite descriptions is entirely linguistic. That is, he is describing only what takes place linguistically (or what is really meant) when we say that we have knowledge by description. He is neither giving a list of those things about which we have descriptive knowledge, nor is he giving a rule of verification to test the truth of this knowledge. He concludes this chapter, however, by making a final epistemological point. Although all knowledge by definite description (knowledge of existence or detailed knowledge) depends upon unique definite descriptions, he argues that these definite descriptions must ultimately reduce to knowledge by acquaintance (58-59). For example, my knowledge that Michael J. Fox plays the role of Alex Keaton is based my reading the credits at the beginning of Family Ties, which involves sense data. Further, my knowledge that he is short is based on an article I read about him in U.S.A. Today, which, again, involves acquaintance with sense data. (37) What is the fundamental principle in the analysis of propositions containing descriptions (M 58)? CHAPTER SIX: ON INDUCTION With the exception of his brief discussion of knowledge by description, Russell's concern so far has been with knowledge by acquaintance, and, specifically, knowledge of sense data. However, humans do more than just receive sense data. I may know from my sense data that I experienced pain after dropping a bowling ball on my toe. As a normal human being, though, I make several inferences from this: (1) my pain was caused by dropping the bowling ball on my toe, (2) if I drop the ball one my toe again, I will experience similar pain, (3) if anyone similarly drops the ball on his toe, he will experience pain. These inferences clearly go beyond what we immediately know from our sense data. What is involved here is the use of general principles, specifically, causality (the ball caused my pain), induction to a particular (a particular act done in the future will yield similar painful results) and inductive generalization (all similar acts will result in similar feelings of pain). Other general principles for Russell include the law of identity, the law of contradiction, and the law excluded middle. These principles are what philosophers frequently call a priori principles, that is, principles which do not depend upon (or go beyond) what we learn from our senses. The issue which concerns Russell is whether we are ever justified in applying these general a priori principles. In this Chapter, Russell focuses on one of these principle: the principle of induction. Any time we expect an event to take place in future on the basis of the past, we are using the principle of induction. For example, our expectation that the sun will rise tomorrow is based on our belief in the laws of motion. And this belief, in turn is based on induction. (38) What is the only reason for believing that the laws of motion will remain in operation (B 61)? (39) What is the real question about induction (T 62)? (40) Before answering this question, Russell provides an explanation for why we use the principle of induction. His explanation is similar to Hume's explanation. Although this explanation does not justify the use of induction, nevertheless, it explains psychologically why we do use this principle. Briefly, what is Russell's explanation (M 62- bottom 63). Returning to the issue of justifying induction, Russell notes that there are two distinct principles of induction. (41) The first principle is usually called induction to a particular since it makes a conclusion about a particular future event. Briefly describe this principle (B 66). (42) The second principle is usually called inductive generalization since it makes a conclusion about all events of a certain kind. Briefly describe this principle (M 67). (43) Why cannot either of these principles of induction be disproved (T 68)? (44) Why, on the other hand, can't either of these principles be proved (B 68)? The fact that induction cannot be proved is usually called the problem of induction. It was Hume who first pointed out that justifying induction is problematic since any attempted justification must necessarily use the same principle of induction which it attempts to prove. Russell recognizes this very same problem. His conclusion is that although we must use general principles, such as these, they are in the end philosophically unjustifiable.