3.2.3 David Hume’s Skepticism

1: Introduction

Background on David Hume and his skepticism

• David Hume: A Scottish philosopher born on May 7, 1711, in Edinburgh, United Kingdom, and died on August 25, 1776.
• Philosophical Empiricism: Hume is best known for his philosophical empiricism, which argues against the existence of innate ideas and states that people only have knowledge of things they experience directly.
• Skepticism: Hume is a prominent figure in the skeptical philosophical tradition, and his skepticism is a significant aspect of his work.
• A Treatise of Human Nature: Hume’s skepticism is mainly presented in his book “A Treatise of Human Nature,” where he aimed to create a total naturalistic “science of man” that explored the psychological basis of human nature.
• Desire over Reason: Hume concluded that desire, rather than reason, dictated human behavior.
• Sentimentalist: Hume was a sentimentalist, maintaining that ethics are not based on abstract moral principles but on feelings.

The importance of Hume’s skepticism in the history of philosophy

• Key Figure: Hume is noted as one of the key figures in the history of Western philosophy and the Scottish Enlightenment.
• Challenging Traditional Views: Hume’s skepticism challenged various aspects of human knowledge, such as induction, the external world, the self, causality, and religion.
• Influence on Later Philosophers: Hume’s skepticism has had a lasting impact on philosophy, influencing later philosophers and shaping modern philosophical debates.

2: Hume’s Skeptical Argument Against Induction

The problem of induction

• Problem of Induction: A philosophical issue that questions the validity of inductive reasoning, which involves drawing general conclusions from specific observations.
• Inductive Reasoning: A type of reasoning where generalizations are made based on specific instances or observations.
• Uncertain Conclusions: The problem of induction highlights that inductive reasoning can lead to uncertain conclusions, as it is impossible to guarantee that future observations will always align with past observations.
• Example: If all observed swans are white, one might conclude that all swans are white. However, this conclusion is uncertain, as it is possible to encounter a non-white swan in the future.

Hume’s argument against induction

• Hume’s Fork: Hume argued that there are two types of knowledge: relations of ideas (analytic) and matters of fact (synthetic).
• Relations of Ideas: Statements that are true by definition and can be known a priori (without experience), such as mathematical truths.
• Matters of Fact: Statements that are true based on experience and observation, such as “the sun will rise tomorrow.”
• Inductive Reasoning and Matters of Fact: Hume argued that inductive reasoning is used to establish matters of fact, but it cannot provide certainty, as it relies on the assumption that the future will resemble the past.
• No Rational Justification: Hume claimed that there is no rational justification for the assumption that the future will resemble the past, as it cannot be proven through relations of ideas or matters of fact.

The assumption that the future will resemble the past

• Uniformity of Nature: The assumption that the future will resemble the past is based on the belief in the uniformity of nature, which states that natural laws and patterns remain constant over time.
• Circular Reasoning: Hume argued that using inductive reasoning to justify the uniformity of nature is circular reasoning, as it assumes the very thing it is trying to prove.
• Custom and Habit: Hume suggested that humans rely on inductive reasoning and the assumption that the future will resemble the past due to custom and habit, rather than rational justification.
• Skeptical Conclusion: Hume’s argument against induction leads to a skeptical conclusion, as it challenges the certainty of knowledge gained through inductive reasoning and highlights the limitations of human understanding.

3: Hume’s Skepticism and the External World

Hume’s views on the existence of external things

• External World: The world outside of one’s own mind and perceptions.
• Indirect Realism: Hume’s view on the external world is often described as indirect realism, which suggests that humans perceive the world indirectly through mental representations or ideas.
• Impressions and Ideas: Hume divided human perceptions into two categories: impressions (direct sensory experiences) and ideas (mental representations of impressions).
• Copy Principle: Hume’s copy principle states that all ideas are derived from and are less vivid copies of impressions.
• Perceptions and External Objects: Hume argued that humans cannot have direct knowledge of external objects, as they only have access to their own perceptions.
• Skepticism: Hume’s views on the external world lead to skepticism, as they challenge the certainty of knowledge about the existence of external things.

The limitations of human senses

• Human Senses: The five senses (sight, hearing, touch, taste, and smell) through which humans perceive the world.
• Perceptual Errors: Hume acknowledged that human senses are prone to errors and can be deceived, leading to false beliefs about the external world.
• Optical Illusions: Hume used examples of optical illusions to demonstrate the limitations of human senses, such as the Müller-Lyer illusion, where two lines of equal length appear to be of different lengths due to the placement of arrowheads at their ends.
• Relativity of Perception: Hume also pointed out the relativity of perception, as different individuals may perceive the same external object differently due to variations in their sensory experiences.

The role of experience in forming beliefs

• Empiricism: Hume was an empiricist, believing that all knowledge is derived from experience.
• Experience and Beliefs: Hume argued that humans form beliefs about the external world based on their experiences and the patterns they observe in their perceptions.
• Causation: Hume suggested that humans infer causal relationships between events based on their experiences of constant conjunction (when two events always occur together).
• Custom and Habit: Hume maintained that humans rely on custom and habit to form beliefs about the external world, as they naturally assume that future experiences will resemble past experiences.
• Skepticism and Experience: Hume’s skepticism about the external world highlights the limitations of human understanding and the reliance on experience in forming beliefs, as it is impossible to guarantee that future experiences will always align with past experiences.

4: Hume’s Skepticism and the Self

Hume’s views on the self and personal identity

• Self: The concept of an individual’s unique identity, consciousness, and personal characteristics.
• Personal Identity: The continuity of the self over time, which allows individuals to recognize themselves as the same person throughout their lives.
• Bundle Theory: Hume proposed the bundle theory of the self, which suggests that the self is not a single, unified entity but rather a collection of perceptions and experiences.
• No Substantial Self: Hume argued that there is no substantial self or enduring personal identity, as humans cannot directly perceive a unified self through introspection.
• Perceptions and Experiences: Hume maintained that the self is merely a collection of perceptions and experiences that are constantly changing and evolving.
• Skepticism: Hume’s views on the self lead to skepticism about the existence of a substantial self and the continuity of personal identity.

The role of memory and experience in understanding the self

• Memory: The cognitive process of storing and recalling past experiences and information.
• Experience: The accumulation of knowledge and understanding gained through direct observation, participation, or perception of events.
• Role of Memory: Hume acknowledged the crucial role of memory in shaping the self and maintaining a sense of personal identity, as it allows individuals to recall past experiences and connect them to their present perceptions.
• Temporal Continuity: Memory provides a sense of temporal continuity, as it enables individuals to recognize themselves as the same person over time, despite the constant changes in their perceptions and experiences.
• Experience and the Self: Hume argued that the self is formed and shaped by experiences, as individuals develop their personal characteristics, beliefs, and values based on their unique life experiences.
• Skepticism and Memory: Hume’s skepticism about the self highlights the limitations of human understanding and the reliance on memory and experience in forming a sense of personal identity, as it is impossible to guarantee the accuracy and completeness of one’s memories and experiences.

5: Hume’s Skepticism and Causality

Hume’s analysis of causality

• Causality: The relationship between cause and effect, where one event or action leads to another.
• Hume’s Approach: Hume analyzed causality from an empirical and skeptical perspective, questioning the certainty of knowledge about cause and effect relationships.
• Constant Conjunction: Hume argued that humans infer causal relationships based on their experiences of constant conjunction, where two events always occur together.
• Cause and Effect: Hume maintained that cause and effect are not directly perceivable but are inferred from the regularity of events.

The problem of necessary connections

• Necessary Connection: The idea that there is a necessary link between cause and effect, such that the cause must always produce the effect.
• Hume’s Critique: Hume challenged the notion of necessary connections, arguing that humans cannot directly perceive or rationally justify the existence of such connections.
• Inductive Reasoning: Hume pointed out that the belief in necessary connections relies on inductive reasoning, which, as discussed earlier, is subject to the problem of induction.
• Skepticism: Hume’s critique of necessary connections leads to skepticism about the certainty of knowledge regarding causality, as it highlights the limitations of human understanding in establishing cause and effect relationships.

The role of experience in understanding causality

• Empiricism: As an empiricist, Hume believed that all knowledge, including knowledge about causality, is derived from experience.
• Experience and Causality: Hume argued that humans form beliefs about causality based on their experiences of constant conjunction and the patterns they observe in events.
• Custom and Habit: Hume maintained that humans rely on custom and habit to infer causal relationships, as they naturally assume that future events will resemble past events.
• Skepticism and Experience: Hume’s skepticism about causality emphasizes the limitations of human understanding and the reliance on experience in forming beliefs about cause and effect relationships, as it is impossible to guarantee that future experiences will always align with past experiences.

6: Comparing Hume’s Skepticism with Other Philosophical Traditions

Academic Skepticism

• Academic Skepticism: A philosophical tradition originating from the Platonic Academy, which questions the possibility of attaining certain knowledge.
• Socrates and Plato: Academic skepticism has its roots in the works of Socrates and Plato, who emphasized the importance of questioning and doubting one’s beliefs.
• Skepticism and Certainty: Academic skeptics argue that humans cannot achieve certainty in their knowledge, as they are limited by their senses and the fallibility of their reasoning.
• Comparison with Hume: Hume’s skepticism shares similarities with academic skepticism in questioning the certainty of human knowledge, but Hume focuses more on the limitations of inductive reasoning and the role of experience in forming beliefs.

Pyrrhonian Skepticism

• Pyrrhonian Skepticism: A philosophical tradition founded by Pyrrho of Elis, which advocates for suspending judgment on all beliefs and embracing a state of doubt.
• Epoché: Pyrrhonian skeptics practice epoché, the suspension of judgment, as a means to achieve tranquility and avoid dogmatism.
• Comparison with Hume: While Hume’s skepticism shares the emphasis on doubt and questioning with Pyrrhonian skepticism, Hume does not advocate for the complete suspension of judgment but rather highlights the limitations of human understanding and the role of custom and habit in forming beliefs.

Cartesian Skepticism

• Cartesian Skepticism: A form of skepticism associated with the French philosopher René Descartes, which focuses on doubting the reliability of one’s senses and the existence of the external world.
• Cogito, ergo sum: Descartes famously concluded that the only certain knowledge is the existence of one’s own mind, as expressed in his statement “Cogito, ergo sum” (I think, therefore I am).
• Method of Doubt: Descartes employed a method of doubt to systematically question all beliefs, aiming to establish a foundation of certain knowledge.
• Comparison with Hume: Hume’s skepticism shares some similarities with Cartesian skepticism in questioning the reliability of the senses and the existence of the external world, but Hume focuses more on the limitations of inductive reasoning and the role of experience in forming beliefs, rather than seeking a foundation of certain knowledge.

7: Hume’s Skepticism and Practical Reason

Hume’s views on practical reason

• Practical Reason: The aspect of human reasoning that deals with decision-making, action, and the pursuit of goals.
• Hume’s Account: Hume argued that practical reason is subordinate to passions or desires, as it is the role of reason to discover the means to achieve the ends determined by desires.
• Reason and Passions: Hume famously stated that “reason is, and ought only to be the slave of the passions,” emphasizing that reason alone cannot motivate action or determine the goals humans pursue.
• Moral Judgments: Hume also applied his views on practical reason to moral judgments, arguing that moral evaluations are based on sentiments or feelings, rather than reason.

The skeptical and instrumentalist readings of Hume’s account of practical reason

• Skeptical Reading: Some interpreters of Hume’s account of practical reason argue that Hume’s skepticism extends to the realm of practical reason, as he questions the ability of reason to determine the ends humans pursue or to motivate action.
• Instrumentalist Reading: Other interpreters emphasize Hume’s instrumentalist view of practical reason, which suggests that reason serves as a tool to help humans achieve their desires and goals, rather than determining those goals or motivating action.
• Debate: The debate between the skeptical and instrumentalist readings of Hume’s account of practical reason highlights the complexity of Hume’s views and the ongoing discussion about the role of reason in human action and moral judgments.

8: Hume’s Skepticism and Religion

Hume’s critique of religious arguments

• Critique of Religious Arguments: Hume critically examined various religious arguments, such as the cosmological argument, the teleological argument, and the ontological argument, questioning their validity and rational basis.
• Cosmological Argument: An argument for the existence of God based on the idea that the universe must have a cause or explanation for its existence. Hume argued that the cosmological argument relies on the assumption of necessary connections, which he had previously critiqued in his analysis of causality.
• Teleological Argument: An argument for the existence of God based on the apparent design and order in the universe. Hume criticized the teleological argument by pointing out that the analogy between the universe and human artifacts is weak and that the argument does not necessarily lead to the existence of a single, all-powerful, and benevolent deity.
• Ontological Argument: An argument for the existence of God based on the concept of God as a perfect being. Hume did not directly address the ontological argument but questioned the ability of reason to establish the existence of God or any necessary being.

The fideistic Christian approach

• Fideism: A religious approach that emphasizes faith over reason in matters of religious belief.
• Christian Fideism: A form of fideism that maintains that Christian beliefs are based on faith and are not subject to rational justification or empirical verification.
• Hume’s Influence: Hume’s skepticism and critique of religious arguments have influenced some fideistic Christian thinkers, who argue that religious beliefs should be grounded in faith rather than reason.
• Faith and Skepticism: While Hume’s skepticism challenges the rational basis of religious arguments, it may also provide support for fideistic approaches that emphasize the importance of faith in religious belief and practice.

9: Hume’s Skepticism and Natural Beliefs

The role of natural beliefs in Hume’s philosophy

• Natural Beliefs: Innate or instinctive beliefs that humans hold without conscious reasoning or justification.
• Hume’s View: Hume acknowledged the existence of natural beliefs, which he considered essential for human survival and functioning.
• Custom and Habit: Hume argued that many natural beliefs, such as the belief in causality and the uniformity of nature, arise from custom and habit rather than rational justification.
• Skepticism and Natural Beliefs: Hume’s skepticism highlights the limitations of human understanding in justifying natural beliefs, but he also recognized the importance of these beliefs in guiding human action and decision-making.

The balance between skeptical attacks and positive theories

• Skeptical Attacks: Hume’s skepticism challenges various aspects of human knowledge, such as induction, the external world, the self, causality, and religion.
• Positive Theories: Despite his skeptical attacks, Hume also offered positive theories and explanations for the formation of beliefs and the functioning of human understanding, such as the role of custom and habit, the influence of experience, and the importance of natural beliefs.
• Balancing Skepticism and Positive Theories: Hume’s philosophy strikes a balance between skepticism and positive theories, as he acknowledges the limitations of human understanding while also providing insights into the processes and mechanisms that underlie human beliefs and actions.
• Hume’s Legacy: Hume’s balanced approach to skepticism and positive theories has contributed to his lasting influence on philosophy, as his work continues to inspire debate and discussion on the nature of human understanding and the role of natural beliefs in shaping human thought and behavior.

10: Responses to Hume’s Skepticism

Criticisms and defenses of Hume’s skepticism

• Criticisms: Hume’s skepticism has been criticized for various reasons, such as its perceived negative implications for human knowledge and understanding, as well as its potential to undermine the foundations of science, morality, and religion.
• Defenses: Defenders of Hume’s skepticism argue that it serves as a valuable reminder of the limitations of human understanding and the importance of humility in the pursuit of knowledge. They also emphasize that Hume’s skepticism does not necessarily lead to complete doubt or inaction, as he acknowledges the role of natural beliefs and custom in guiding human behavior.
• Debate: The debate surrounding Hume’s skepticism reflects the ongoing discussion about the role of skepticism in philosophy and the extent to which human understanding can be trusted or relied upon.

The influence of Hume’s skepticism on later philosophers

• Immanuel Kant: Hume’s skepticism is often credited with inspiring the German philosopher Immanuel Kant, who sought to address the limitations of human understanding by developing a critical philosophy that distinguished between the phenomenal and noumenal worlds.
• Logical Positivism: Hume’s skepticism and empiricism also influenced the development of logical positivism, a philosophical movement that emphasized the importance of empirical evidence and scientific methods in the pursuit of knowledge.
• Pragmatism: Hume’s emphasis on the role of custom, habit, and natural beliefs in shaping human understanding has been seen as a precursor to the pragmatist tradition, which focuses on the practical consequences of beliefs and actions rather than abstract philosophical principles.
• Contemporary Philosophy: Hume’s skepticism continues to be a topic of interest and debate in contemporary philosophy, as philosophers grapple with the implications of his skeptical arguments for various aspects of human knowledge and understanding.

11: Hume’s Skepticism in Contemporary Philosophy

The relevance of Hume’s skepticism in modern philosophical debates

• Hume’s Legacy: Hume’s skepticism continues to be influential in contemporary philosophy, as his arguments and insights remain relevant to various aspects of human knowledge and understanding.
• Epistemology: Hume’s skepticism has had a lasting impact on epistemology, the study of knowledge, as it raises important questions about the limits of human understanding and the role of experience, custom, and habit in forming beliefs.
• Philosophy of Science: Hume’s critique of induction and causality has implications for the philosophy of science, as it challenges the certainty of scientific knowledge and the foundations of empirical inquiry.
• Ethics and Moral Philosophy: Hume’s views on practical reason and the role of sentiments in moral judgments have influenced contemporary debates in ethics and moral philosophy, particularly in the areas of moral psychology and metaethics.

The ongoing discussion of Hume’s arguments and their implications

• Debates and Interpretations: Hume’s arguments continue to be the subject of ongoing discussion and debate in contemporary philosophy, as scholars grapple with the implications of his skepticism for various aspects of human knowledge and understanding.
• Responses to Hume’s Skepticism: Philosophers have developed various responses to Hume’s skepticism, ranging from attempts to refute his arguments and defend the possibility of certain knowledge to embracing his insights and developing alternative approaches to understanding and inquiry.
• Influence on Later Philosophers: Hume’s skepticism has inspired and influenced later philosophers, such as Immanuel Kant, who sought to address the limitations of human understanding by developing a critical philosophy that distinguished between the phenomenal and noumenal worlds.
• Contemporary Relevance: Hume’s skepticism remains relevant in contemporary philosophy, as it serves as a reminder of the limitations of human understanding and the importance of humility in the pursuit of knowledge, while also providing insights into the processes and mechanisms that underlie human beliefs and actions.

12: Conclusion

In conclusion, Hume’s skepticism has had a lasting impact on various aspects of philosophy, raising important questions about the limits of human understanding and the role of experience, custom, and habit in forming beliefs. His arguments continue to be influential in contemporary philosophical debates, inspiring responses and alternative approaches to understanding and inquiry. As a reminder of the limitations of human understanding and the importance of humility in the pursuit of knowledge, Hume’s skepticism remains relevant and serves as a foundation for ongoing discussions in philosophy. The way forward is to continue engaging with Hume’s insights and exploring their implications for our understanding of knowledge, science, ethics, and other areas of philosophical inquiry.

1. Analyze the differences and similarities between John Locke’s and George Berkeley’s criteria for determining the reality of something, considering their respective theories of knowledge. (250 words)
2. Discuss the implications of David Hume’s skepticism on the possibility of attaining certain knowledge, and compare his views with those of Locke and Berkeley. (250 words)
3. Examine the role of primary and secondary qualities in Locke’s theory of knowledge, and evaluate Berkeley’s critique of this distinction. (250 words)
4. Compare and contrast the views of Locke, Berkeley, and Hume on the nature and limits of human knowledge, particularly in relation to the role of sense experience and reason. (250 words)
5. Assess the impact of the empiricist tradition, as represented by Locke, Berkeley, and Hume, on modern epistemology and its influence on subsequent philosophers. (250 words)