Notebook for "Critical Thinking"
Dauer, Francis Watanabe (1989). Critical Thinking: An Introduction to Reasoning. Oxford University Press.

Table of Contents

1. License

(C) Copyright 2022 by David T. O'Toole

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3. Reading plan [14%]

  • Read Chapter 1
  • Read Chapter 2 [57%]
    • 2.0
    • 2.1
    • 2.2
    • 2.3
    • 2.4
    • 2.5
    • 2.6
  • Read Chapter 3 [0%]
    • 3.0
    • 3.1
    • 3.2
    • 3.3
    • 3.4
    • 3.5
    • 3.6
    • 3.7
    • 3.8
    • 3.9
  • Read Chapter 4 [0%]
    • 4.0
    • 4.1
    • 4.2
    • 4.3
    • 4.4
    • 4.5
    • 4.6
    • 4.7
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    • 5.0
    • 5.1
    • 5.2
    • 5.3
    • 5.4
    • 5.5
  • Read Chapter 6 [0%]
    • 6.0
    • 6.1
    • 6.2
    • 6.3
    • 6.4
    • 6.5
    • 6.6
  • Read Chapter 7 [0%]
    • 7.0
    • 7.1

4. Notes and exercises

4.1. Introduction to Critical Thinking

Assessing truth values:

  • Gather and isolate the unproblematic claims
  • Reason from the unproblematic to the truth or falsehood (or likelihood thereof) of the problematic claims

In order to do this, we need:

  • Maxims to help us determine what is unproblematic
  • Canons to determine what reasons are good
  • Maxims to determine meanings of propositions

4.2. Accepting the Unproblematic

"We simply have to accept certain claims as unproblematic in our daily lives even if we cannot rule out the possibility of error."

  • Unproblematic claims are not infallible.

4.2.1. A short account of the unproblematic

Five kinds of unproblematic claims:

Abbreviation Type How/Who Example
OB observational oneself Headache
PF particular factual experts Date of Kennedy assassination
INT intuitive reflection logic
SM general science and math experts Pythagorean theorem
CS general common sense combination see below

Common Sense (CS) claim C has for person P at time t has the following characteristics:

  • P has confirming evidence that C is the case at time t
  • P has no evidence disconfirming that C is the case
  • Knowledgeable/expert people P has met are in agreement that C is the case Exercises
  • (a) OB, only introspection needed.
  • (b) OB, only memory needed.
  • (c) SM, doctors and researchers.
  • (d) INT, reflection on experience with tallness.
  • (e) CS, general experience that bikes are faster.
  • (f) Problematic
  • (g) PF, newspaper records
  • (h) SM, scientists
  • (i) PF, astronomers
  • (j) SM, mathematicians

4.2.2. Candidates for unproblematic acceptance

Abbreviation Type Content Direct Access Transmitted Access
OB observational What was observed Observer at time of observation Transmission is presumable
PF particular factual Uncontroversial particular facts Made available by an expert source at the time of accepting the claim Transmission is presumable.
INT intuitive Reflection shows it must be true "Content" easily ascertained at the time of accepting the claim N/A
SM general science and math General laws of science and mathematics Made available by an expert source at the time of accepting the claim Transmission is presumable.
CS general common sense Personally confirmed, generally acknowledged, undisconfirmed generalization of common sense With the help of memory, content is ascertained at the time of accepting the claim N/A Exercises
  • 1
    • (a) Yes: she sees the attack directly
    • (b) No: she only thinks it's probably the same knife
    • (c) No: she only thinks this
    • (d) No: she only assumes this
    • (e) No: this is only the rumor
    • (f) Yes: she is the authority on her mental state
    • (g) Yes: she is the authority on what she wanted to do
    • (h) Yes: she heard him say these things
    • (i) No: this is an assumption
  • 2
    • (a) Yes: the reporter is taking this as a fact
    • (b) Yes: expert source claims this to reporter
    • (c) No: his mental state is not accessible
    • (d) No: his mental state is not accessible
    • (e) No: this is an interpretation
  • 3
    • (a) Yes: this is acknowledged by experts
    • (b) No: this is an interpretation of motives
    • (c) Yes: claim of experts
    • (d) No: this is an evaluative claim
    • (e) No: this is an evaluative claim
  • 4
    • (a) Yes: this is determined by date of last show
    • (b) No: this is a judgment
    • (c) Yes: clothing was observed
    • (d) No: this is evaluative
    • (e) No: this is an evaluation
    • (f) No: this is an evaluation
    • (g) Yes: factual observed
    • (h) No: her mental state is not visible
    • (i) No: this is a conjecture
    • (j) Yes: observed the walkouts
    • (k) No: this is the claim of a critic
    • (l) No: this is a subjective claim
  • 5
    • (a) OB: i can observe my own state
    • (b) Problematic
    • (c) Problematic (memory)
    • (d) Problematic
    • (e) Problematic
    • (f) Problematic
    • (g) CS: experience and reason
    • (h) INT: reflection
    • (i) SM: physics
    • (j) SM: physics
    • (k) PF: fact

4.2.3. Transmission of claims

OB, PF, and SM claims can be transmitted by:

  • Memory
  • Expert testimony
  • Nonexpert testimony (with qualifications)

A remembered claim can be unproblematic if it is:

  • Recently acquired,
  • Memorable, or
  • Corroborated

There are degrees of corroboration and degrees of memorability.

  • Say claim "C" is unproblematic
  • But claim "C has been corroborated/recently acquired/memorable" may still be problematic

Nonexpert testimony is appropriately initiated when either:

  • A source is given, or
  • An equally good source is available Exercises
  • 1
    • (a) OB, memorable
    • (b) OB, memorable never attended this class
    • (c) PF, corroborated by news reports
    • (d) SM, corroborated by scientists and experience
    • (e) PF, news reports / historians
    • (f) PF, corroborated
  • 2
    • (a) OB, memorable, he observed this directly
    • (b) Problematic
    • (c) Problematic
    • (d) OB, direct expression
  • 3
    • (a) INT, direct; easy to understand
    • (b) SM, transmitted: proof not easy to hold in mind
    • (c) SM, transmitted: proved by experiments
    • (d) SM, transmitted: law of physics
    • (e) SM, transmitted: proof not easy to hold in mind
    • (f) PF, transmitted: cannot experience directly
    • (g) Problematic
    • (h) CS in 1989, but problematic now
    • (i) PF, transmitted: scientists
    • (j) PF, transmitted: astronomers
    • (k) PF, direct: newspaper

4.2.4. Grounds for doubting a candidate

4.2.5. Unproblematic claims

4.2.6. Related fallacies

4.3. Deductive Reasoning

4.3.1. Preliminaries

4.3.2. Deductive validity: a general informal account

4.3.3. Truth functional logical forms

4.3.4. Other logical properties and truth table analyses

4.3.5. Toward a method for determining deductive validity

4.3.6. Expanding the list of valid argument types

4.3.7. Translating logical forms

4.3.8. Beyond simple chain arguments

4.3.9. Summary and deductive fallacies

4.4. Analyzing argumentative passages

4.4.1. Types of reasons and degrees of justification

4.4.2. Deductive validity and degrees of justification

4.4.3. Extracting an outline of the argument

4.4.4. Supplying missing premises

4.4.5. Plausibility assessments

4.4.6. Auxiliary aids

4.4.7. Related fallacies

4.5. Nondemonstrative arguments

4.5.1. Nondemonstrative legitimacy as the inference to the best explanation

4.5.2. Determining the best explanation

4.5.3. Varieties of nondemonstrative arguments

4.5.4. Inferring explanatory generalizations

4.5.5. Mill's methods and inferring descriptive generalizations

4.6. Language and the Levels of Meaning

4.6.1. Introduction and use/mention confusions

4.6.2. The level of syntax

4.6.3. The level of semantics

4.6.4. The level of illocutionary forces

4.6.5. The level of pragmatics

4.6.6. Two additional dimensions of meaning

4.7. Glimpses beyond Critical Thinking

4.7.1. The finer structure of statements

4.8. Probabilities

5. TODO Study one section of CT

  • State "DONE" from "TODO" [2022-12-12 Mon 20:39]
  • State "DONE" from "TODO" [2022-12-11 Sun 12:57]
  • State "DONE" from "TODO" [2022-12-10 Sat 19:00]
  • State "DONE" from "TODO" [2022-12-09 Fri 18:00]