Argument Mapping Skill
Master the art of reconstructing, visualizing, and evaluating the logical structure of arguments.
Why Map Arguments?
Argument mapping serves several purposes:
- •Clarify: Make implicit structure explicit
- •Evaluate: Assess validity and soundness systematically
- •Communicate: Present complex arguments visually
- •Critique: Identify weaknesses and hidden assumptions
- •Steelman: Ensure fair representation of opposing views
Basic Argument Structure
Components of an Argument
| Component | Definition | Example |
|---|---|---|
| Conclusion | The claim being argued for | "Socrates is mortal" |
| Premise | A reason supporting the conclusion | "All men are mortal" |
| Inference | The logical move from premises to conclusion | "Therefore..." |
| Assumption | Unstated premise needed for validity | (Often hidden) |
Simple Argument Form
P1: [Premise 1] P2: [Premise 2] ------------------- C: [Conclusion]
Example:
P1: All men are mortal P2: Socrates is a man ------------------- C: Socrates is mortal
The Toulmin Model
Stephen Toulmin's model captures the nuanced structure of real-world arguments.
Six Components
QUALIFIER
│
▼
GROUNDS ──────────► CLAIM ◄─────────── REBUTTAL
│ ▲ │
│ │ │
▼ │ ▼
WARRANT ◄──────── BACKING (Unless...)
| Component | Definition | Example |
|---|---|---|
| Claim | The conclusion/assertion | "We should ban smoking in restaurants" |
| Grounds | Evidence/data supporting claim | "Secondhand smoke causes cancer" |
| Warrant | Principle connecting grounds to claim | "We should prevent cancer-causing exposures" |
| Backing | Support for the warrant itself | "Preventing harm is a core purpose of public policy" |
| Qualifier | Degree of certainty | "Probably," "Certainly," "Presumably" |
| Rebuttal | Conditions where claim fails | "Unless economic harm outweighs health benefits" |
Toulmin Diagram Template
┌─────────────────────────────────────────────────────────────────────┐ │ │ │ CLAIM: [Central thesis/conclusion] │ │ Qualifier: [Certainly/Probably/Possibly] │ │ │ │ ──────────────────────────────────────────────────────────────── │ │ │ │ GROUNDS: │ REBUTTAL: │ │ [Evidence/facts/data] │ Unless [exception conditions] │ │ │ │ │ ──────────────────────────────────────────────────────────────── │ │ │ │ WARRANT: │ │ [Principle that licenses inference from grounds to claim] │ │ │ │ ──────────────────────────────────────────────────────────────── │ │ │ │ BACKING: │ │ [Support for the warrant] │ │ │ └─────────────────────────────────────────────────────────────────────┘
Argument Reconstruction Protocol
Step 1: Identify the Conclusion
What is the main claim being defended?
Indicator words: therefore, thus, hence, so, consequently, it follows that, we can conclude
If not explicit: What would the speaker want you to believe/do?
Step 2: Find the Premises
What reasons are given for the conclusion?
Indicator words: because, since, for, given that, as shown by, the reason is
List them: Number each premise explicitly (P1, P2, P3...)
Step 3: Make Implicit Premises Explicit
What unstated assumptions are needed for the argument to work?
Test: If we add this premise, does the argument become valid?
Charity: Choose the most reasonable implicit premises
Step 4: Analyze the Structure
How do the premises relate?
Linked premises: Work together (all needed)
P1 + P2
│
▼
C
Convergent premises: Independent support (each sufficient)
P1 P2
\ /
\ /
C
Serial/Chain arguments: One supports another
P1
│
P2
│
C
Step 5: Evaluate
- •Validity: Does conclusion follow from premises?
- •Soundness: Are premises actually true?
- •Strength (inductive): How probable is conclusion given premises?
Diagramming Conventions
Standard Notation
┌─────┐ │ P1 │ ← Premise (box) └──┬──┘ │ ▼ ┌─────┐ │ C │ ← Conclusion (box) └─────┘
Linked vs. Convergent
Linked (all premises needed together):
┌─────┐ ┌─────┐
│ P1 │───│ P2 │
└──┬──┘ └──┬──┘
└────┬────┘
▼
┌─────┐
│ C │
└─────┘
Convergent (independent support):
┌─────┐ ┌─────┐
│ P1 │ │ P2 │
└──┬──┘ └──┬──┘
│ │
└─────┬───────┘
▼
┌─────┐
│ C │
└─────┘
Sub-Arguments
When a premise is itself supported:
┌─────┐ │ P1a │ ← Sub-premise └──┬──┘ ▼ ┌─────┐ │ P1 │ ← Intermediate conclusion / Premise for main argument └──┬──┘ │ ┌──┴──┐ │ P2 │ └──┬──┘ ▼ ┌─────┐ │ C │ ← Main conclusion └─────┘
Objections and Rebuttals
┌─────┐
│ P1 │
└──┬──┘
▼
┌─────┐ ┌─────────┐
│ C │ ◄─ ✗ ───│Objection│
└─────┘ └────┬────┘
│
┌────▼────┐
│ Rebuttal│
└─────────┘
Dialectical Tree Format
For multi-position debates:
THESIS: [Main Position A]
│
├── Support 1: [Argument for A]
│ ├── Evidence 1a
│ └── Evidence 1b
│
├── Support 2: [Another argument for A]
│
└── ANTITHESIS: [Opposing Position B]
│
├── Objection to Support 1: [Why it fails]
│
├── Objection to Support 2: [Why it fails]
│
└── Positive argument for B
│
└── SYNTHESIS: [Higher-level resolution]
│
├── What's preserved from A
├── What's preserved from B
└── What's new
Common Argument Patterns
Deductive Patterns
Modus Ponens:
P1: If A, then B P2: A --------------- C: B
Modus Tollens:
P1: If A, then B P2: Not B --------------- C: Not A
Disjunctive Syllogism:
P1: A or B P2: Not A --------------- C: B
Hypothetical Syllogism:
P1: If A, then B P2: If B, then C --------------- C: If A, then C
Reductio ad Absurdum:
P1: Assume A (for contradiction) P2: A leads to contradiction B & not-B --------------- C: Not A
Inductive Patterns
Generalization:
P1: Sample S has property P P2: Sample S is representative of population X --------------- C: (Probably) All X have property P
Analogy:
P1: A has properties F, G, H P2: B has properties F, G P3: A has property X --------------- C: (Probably) B has property X
Inference to Best Explanation:
P1: Phenomenon P is observed P2: Hypothesis H would explain P P3: H is the best available explanation --------------- C: (Probably) H is true
Philosophical Argument Patterns
Conceivability Argument:
P1: X is conceivable P2: If conceivable, then possible --------------- C: X is possible
Counterexample:
P1: Thesis T claims all X are Y P2: Case C is X but not Y --------------- C: Thesis T is false
Thought Experiment:
P1: In scenario S, intuition I is strong P2: If I is correct, then principle P --------------- C: Principle P
Hidden Assumption Detection
Method 1: Gap Analysis
- •State the premises
- •State the conclusion
- •Ask: What must be true for this inference to work?
- •The answer is the hidden assumption
Method 2: Negation Test
- •Negate a potential assumption
- •If the argument fails, the assumption was needed
Method 3: Charity + Validity
- •Assume the argument is intended to be valid
- •What premise would make it valid?
- •That's the most charitable hidden assumption
Common Hidden Assumptions
| Type | Example |
|---|---|
| Empirical | Facts about the world assumed without evidence |
| Normative | Value judgments assumed without defense |
| Conceptual | Definitions assumed without clarification |
| Background | Shared context assumed without statement |
| Scope | Universality assumed without justification |
Evaluation Criteria
For Deductive Arguments
| Criterion | Question | Assessment |
|---|---|---|
| Validity | Does conclusion follow necessarily? | Yes/No |
| Soundness | Are all premises true? | Yes/No/Unknown |
| Completeness | Are hidden premises stated? | Yes/Partially/No |
For Inductive Arguments
| Criterion | Question | Assessment |
|---|---|---|
| Strength | How probable is conclusion given premises? | Strong/Moderate/Weak |
| Cogency | Are premises true AND argument strong? | Yes/No |
| Sample quality | Is evidence representative? | Yes/No |
Output Templates
Standard Reconstruction
## Argument Reconstruction: [Topic/Source] ### Conclusion [State the main claim being argued for] ### Explicit Premises P1: [First stated premise] P2: [Second stated premise] P3: [Third stated premise] ### Hidden Premises H1: [First unstated assumption needed for validity] H2: [Second unstated assumption] ### Argument Structure [Diagram showing how premises relate to conclusion] ### Evaluation - **Validity**: [Valid/Invalid—explain] - **Soundness**: [Sound/Unsound/Unknown—explain] - **Key weakness**: [Most vulnerable point] ### Dialectical Context [How this argument relates to the broader debate]
Debate Map
## Debate Map: [Topic] ### Question at Issue [The central question being debated] ### Position A: [Label] **Thesis**: [Main claim] **Arguments**: 1. [Argument 1] - Objection: [Counter] - Reply: [Response] 2. [Argument 2] ### Position B: [Label] **Thesis**: [Main claim] **Arguments**: 1. [Argument 1] 2. [Argument 2] ### Points of Agreement - [Shared premise 1] - [Shared premise 2] ### Core Disagreement [What the debate ultimately turns on] ### Assessment [Which position is stronger and why]
Integration with Other Skills
- •philosophical-analyst: Use mapping in step 2 (argument reconstruction)
- •symposiarch: Map arguments during debate management
- •thought-experiments: Map the argument structure of thought experiment cases
- •devils-advocate: Identify weak premises in argument maps
Reference Files
- •
patterns.md: Comprehensive catalog of argument patterns - •
diagramming.md: Extended diagramming conventions and tools