42 pages • 1 hour read
Bertrand RussellThe Problems of Philosophy
Nonfiction | Book | Adult | Published in 1912A modern alternative to SparkNotes and CliffsNotes, SuperSummary offers high-quality Study Guides with detailed chapter summaries and analysis of major themes, characters, and more.
Chapters 4-6Chapter Summaries & Analyses
Chapter 4 Summary: “Idealism”
Russell devotes his attention to dismantling arguments for idealism. He explains that different philosophers have varying versions of the same principle: that physical objects exist within the mind. Russell cautions against immediately dismissing idealism and recommends following the logic of previous arguments within the philosophical field. Physical objects produce sense data in the mind, but this does not speak to the true nature of the object. The sensations of the external world vary from person to person. Therefore, sense data can only correspond to the physical object.
Philosopher George Berkeley used logical arguments to prove that physical objects are entirely mental. Russell explains that these arguments have some validity, but they do not follow the thread of logic all the way to the end. Berkeley proposed that sense data is the only existence that humans can be assured of, existing entirely within the mind. When humans cease interacting with the physical object, it does not disappear. This is because it exists within the mind of God. Therefore, the external world is made up of the interaction between human ideas and the ideas of God.
Russell agrees that the human experience of sense data is subjective. However, he challenges Berkeley’s use of “idea” by explaining that knowledge emerges from the apprehension of a physical object. A distinct difference between the object and the act of apprehension suggests that both are needed to produce knowledge: “If we say that the things known must be in the mind, we are either unduly limiting the mind’s power of knowing, or we are uttering a mere tautology” (23). Knowledge that emerges independently of a physical object occurs through description, a concept explained further in Chapter 5.
Chapter 5 Summary: “Knowledge by Acquaintance and Knowledge by Description”
Russell distinguishes between knowledge of things and knowledge of truths. Knowledge of things is comprised of sense data from apprehending physical objects and descriptions. The knowledge of truths is aligned with belief and conviction. Knowledge of things is broken into two parts: acquaintance and description. The former describes a direct awareness of a physical object, such as the table in Chapter 1. This form of knowledge is subjective, private, and straightforward.
Knowledge by description occurs in Russell’s writing of the table itself. By recounting the sense data of the table, Russell produces knowledge by description for the reader. However, the reader will not be able to produce this knowledge unless they have previous personal experience, or acquaintance, with similar sense data.
Knowledge of truth extends beyond these two types of knowledge of things. If humans only understood the world through sense data, either by description or direct acquaintance with the physical object, their knowledge would be extremely limited. For example, exclusively experiencing the world this way would eradicate one’s understanding of the past because those sensory impressions are long gone. Knowledge of truths is a deeper level of knowing, comprised of abstract ideas called universals.
Acquaintance beyond the physical object is broken into two parts: memory and introspection. Memory allows the individual to access sense data from the past. Introspection is derived from awareness—awareness of things and awareness of the self. Russell clarifies that self-consciousness does not mean consciousness of the self. Instead, self-consciousness, like awareness of things, is derived from recognizing a distinction between one thing and another. Knowledge of the self occurs because the individual is acquainted with the “I” in relation to the rest of the world. Russell summarizes these distinctions to emphasize the pervasive nature of acquaintance in all forms of knowledge:
We have acquaintance in sensation with the data of the outer senses, and in introspection with the data of what we may be called the inner sense—thoughts, feelings, desires, etc.; we have acquaintance in memory with things which have been data either of the outer senses or of the inner sense. Further, it is probable, though not certain, that we have acquaintance with Self, as that which is aware of things or has desires toward things (29).
Acquaintance with universals, such as the concepts of diversity or community, is referred to as “conceiving.” Russell uses linguistics to break down the difference between universals and direct ideas through description. For example, “a man” is a universal. Russell explains that a universal that people are aware of is called a “concept.” However, the description “a man with a bowtie” is a definite description. Knowledge by description allows humans to communicate with one another and transfer knowledge, moving beyond a private experience of the physical world to a collective one.
Chapter 6 Summary: “On Induction”
If humans were limited to sense data, their experience of the world would be restricted and dangerous. For example, humans understand that thunder is connected to lighting. They understand this based on their memory of past sense data and their ability to draw connections. Russell introduces the principle of induction, which humans use to make predictions about the future and the world. Humans believe that the sun will rise in the morning based on past experience; the sun has risen every morning previously. The principle of induction is built on a system of probability. The more frequently a human experiences a connection—such as the relationship between thunder and lightning—the more probable it is that the two are associated. This also increases the probability that the human will experience the same association in the future.
However, Russell highlights a problem with the logic of induction. The fact that the sun has risen every morning in the past is no guarantee that it will rise in the future. He uses the example of a butchered chicken to illustrate this idea. The chicken has no reason to believe that its interaction with a farmer will consist of anything other than being fed by the farmer; then, to the chicken’s surprise, the farmer one day decides to butcher the chicken. Russell explains that humans’ associations often create logical problems. If a person only ever sees white swans, that person may assume that all swans are white. Despite the problems with induction, Russell asserts that it is necessary to exist within everyday life and develop sound scientific reasoning.
Chapters 4-6 Analysis
Russell opens this section with a discussion of idealism and previous philosophers’ interpretations of it. He cites the philosopher George Berkeley, who was alive during the 17th and 18th centuries. Berkeley was a Bishop in the Anglican Church, and his ideologies are firmly rooted in theology. He proposed that object permanence occurs because the external world is an idea produced in God’s mind. Russell, in contrast, was a well-known atheist, and this informs his philosophy as he challenges Berkeley. His religious views often got him into trouble and even led to his dismissal from several positions. At Trinity College of Cambridge, Russell was declined the offer of a fellowship because he refused to pretend to be a devout Christian. Therefore, the argument that the physical world is constructed within the mind of God was not enough for the logical mathematician. For Russell, The Relationship Between Perception and Reality is unrelated to religion, and the atheist subtext of his writing reinforces his emphasis on logic and accessibility.
Another aspect of Russell’s accessible tone is his distillation of complex concepts into single words or pithy phrases. Russell breaks down knowledge into different categories, relating each to perception or what Russell refers to as “acquaintance.” Other forms include knowledge of truth and knowledge by description. In each case, he uses common words instead of philosophical jargon to explain his arguments. This suggests that he believes in The Value of Philosophy for the layman and not just the expert.
In this section, he argues that all forms of knowledge have restrictions, hence exploring the theme of The Nature and Limits of Human Knowledge. Chapter 6 emphasizes the limitations by exploring how humans use induction to make assumptions and predictions about their own lives and the physical world. Russell’s swan analogy provides a simple way of understanding how human knowledge through probability is limited. A person who has only ever seen white swans may deduce that all swans are white. However, when that person is confronted with a black swan, their previous assumption is shattered.
Russell asserts that induction is a necessary part of everyday life and science. Without the fragile connections formed through induction, humans would struggle to make sense of the world. Russell’s argument was later challenged by Karl Popper, who proposed in his 1934 book The Logic of Scientific Discovery that the function of science is to reject assumptions and focus, instead, on verifying falsifiability.
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