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Table of contents
  1. Preface
  2. 1 Introduction to Philosophy
    1. Introduction
    2. 1.1 What Is Philosophy?
    3. 1.2 How Do Philosophers Arrive at Truth?
    4. 1.3 Socrates as a Paradigmatic Historical Philosopher
    5. 1.4 An Overview of Contemporary Philosophy
    6. Summary
    7. Key Terms
    8. References
    9. Review Questions
    10. Further Reading
  3. 2 Critical Thinking, Research, Reading, and Writing
    1. Introduction
    2. 2.1 The Brain Is an Inference Machine
    3. 2.2 Overcoming Cognitive Biases and Engaging in Critical Reflection
    4. 2.3 Developing Good Habits of Mind
    5. 2.4 Gathering Information, Evaluating Sources, and Understanding Evidence
    6. 2.5 Reading Philosophy
    7. 2.6 Writing Philosophy Papers
    8. Summary
    9. Key Terms
    10. References
    11. Review Questions
    12. Further Reading
  4. 3 The Early History of Philosophy around the World
    1. Introduction
    2. 3.1 Indigenous Philosophy
    3. 3.2 Classical Indian Philosophy
    4. 3.3 Classical Chinese Philosophy
    5. Summary
    6. Key Terms
    7. References
    8. Review Questions
    9. Further Reading
  5. 4 The Emergence of Classical Philosophy
    1. Introduction
    2. 4.1 Historiography and the History of Philosophy
    3. 4.2 Classical Philosophy
    4. 4.3 Jewish, Christian, and Islamic Philosophy
    5. Summary
    6. Key Terms
    7. References
    8. Review Questions
    9. Further Reading
  6. 5 Logic and Reasoning
    1. Introduction
    2. 5.1 Philosophical Methods for Discovering Truth
    3. 5.2 Logical Statements
    4. 5.3 Arguments
    5. 5.4 Types of Inferences
    6. 5.5 Informal Fallacies
    7. Summary
    8. Key Terms
    9. References
    10. Review Questions
    11. Further Reading
  7. 6 Metaphysics
    1. Introduction
    2. 6.1 Substance
    3. 6.2 Self and Identity
    4. 6.3 Cosmology and the Existence of God
    5. 6.4 Free Will
    6. Summary
    7. Key Terms
    8. References
    9. Review Questions
    10. Further Reading
  8. 7 Epistemology
    1. Introduction
    2. 7.1 What Epistemology Studies
    3. 7.2 Knowledge
    4. 7.3 Justification
    5. 7.4 Skepticism
    6. 7.5 Applied Epistemology
    7. Summary
    8. Key Terms
    9. References
    10. Review Questions
    11. Further Reading
  9. 8 Value Theory
    1. Introduction
    2. 8.1 The Fact-Value Distinction
    3. 8.2 Basic Questions about Values
    4. 8.3 Metaethics
    5. 8.4 Well-Being
    6. 8.5 Aesthetics
    7. Summary
    8. Key Terms
    9. References
    10. Review Questions
    11. Further Reading
  10. 9 Normative Moral Theory
    1. Introduction
    2. 9.1 Requirements of a Normative Moral Theory
    3. 9.2 Consequentialism
    4. 9.3 Deontology
    5. 9.4 Virtue Ethics
    6. 9.5 Daoism
    7. 9.6 Feminist Theories of Ethics
    8. Summary
    9. Key Terms
    10. References
    11. Review Questions
    12. Further Reading
  11. 10 Applied Ethics
    1. Introduction
    2. 10.1 The Challenge of Bioethics
    3. 10.2 Environmental Ethics
    4. 10.3 Business Ethics and Emerging Technology
    5. Summary
    6. Key Terms
    7. References
    8. Review Questions
    9. Further Reading
  12. 11 Political Philosophy
    1. Introduction
    2. 11.1 Historical Perspectives on Government
    3. 11.2 Forms of Government
    4. 11.3 Political Legitimacy and Duty
    5. 11.4 Political Ideologies
    6. Summary
    7. Key Terms
    8. References
    9. Review Questions
    10. Further Reading
  13. 12 Contemporary Philosophies and Social Theories
    1. Introduction
    2. 12.1 Enlightenment Social Theory
    3. 12.2 The Marxist Solution
    4. 12.3 Continental Philosophy’s Challenge to Enlightenment Theories
    5. 12.4 The Frankfurt School
    6. 12.5 Postmodernism
    7. Summary
    8. Key Terms
    9. References
    10. Review Questions
  14. Index

5.1 Philosophical Methods for Discovering Truth

Logic is the study of reasoning and is a key tool for discovering truth in philosophy and other disciplines. Early philosophers used dialectics—reasoned debates with the goal of getting closer to the truth—to practice and develop reason. Dialectics usually start with a question. An interlocuter offers an answer to the question, which is then scrutinized by all participants. Early forms of arguments are evident in written dialogues. Arguments are reasons offered in support of a conclusion. We use logic to test hypotheses in philosophy and other domains. There are laws of logic—the law of noncontradiction and the law of the excluded middle. Laws of logic can be thought of as rules of thought. Logical laws are rules that underlie thinking itself. The rules or laws of logic are normative—they describe how we ought to reason.

5.2 Logical Statements

Logical statements can be conditionals or universal affirmative statements. Both are important since they express the important logical relations (also called “conditions”) of necessity and sufficiency. If something is sufficient, it is always sufficient for something else. And if something is necessary, it is always necessary for something else. If you want to prove that a conditional or universal affirmative statement is false (which is to also prove that the necessary and sufficient conditions they express do not hold), then you must offer a counterexample.

5.3 Arguments

An argument is a set of reasons offered in support of a conclusion. The reasons are called premises, and they are meant to logically support the conclusion. Identifying the premises involves critically identifying what is meant to be evidence for the conclusion. Both the premises and conclusion can be indicated by phrases and words. Evaluations of arguments take place on two levels: assessing truth and assessing logic. Logic and truth are separate features of arguments. Logical assessment involves determining whether the truth of the premises do support the conclusion. Logically good arguments contain inferences—a reasoning process that leads from one idea to another, through which we formulate conclusions—where the inference does support the conclusion.

5.4 Types of Inferences

There are three different types of inferences: deductive, inductive, and abductive. Deductive inferences, when valid, guarantee the truth of their conclusions. Inductive inferences, when strong, offer probable support for the conclusion. And good abductive inferences offer probable support for their conclusions. Deductive inferences that cannot guarantee the truth of their conclusions are called invalid. A counterexample can be offered to prove that a deductive inference is invalid. Inductive inferences involve using observations based on experience to draw general conclusions about the world. Abductive inferences involve offering explanations for accepted evidence. Abduction is sometimes called “inference to the best explanation.”

5.5 Informal Fallacies

A fallacy is a poor form of reasoning. Fallacies that cannot be reduced to the structure of an argument are called informal fallacies. There are many types of informal fallacies, which can be sorted into four general categories according to how the reasoning fails. These categories are fallacies of relevance, fallacies of weak induction, fallacies of unwarranted assumption, and fallacies of diversion. A fallacy of relevance occurs when the arguer presents evidence that is not relevant for logically establishing their conclusion. The fallacies of weak induction occur when the evidence used is relevant but is too weak to support the desired conclusion. The fallacies of unwarranted assumption occur when an argument assumes, as evidence, some reason that requires further justification. The fallacies of diversion occur when the arguer attempts to distract the attention of the audience from the argument at hand.

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