critical-argumentation

Critical Argumentation

Formal logic tells you when an argument is valid given its premises. It does not tell you whether the premises are true, whether the argument is relevant, whether it is charitable, or whether it deserves a response. Those are questions of critical argumentation -- the practical discipline of engaging with arguments in the form they actually appear: in prose, in speech, in debate, in ordinary disagreement. This skill covers how to identify real arguments, evaluate them fairly, reconstruct them at their best, and build arguments of your own that others can engage with productively.

Agent affinity: russell (critical tradition), langer (pedagogy), quine (linguistic precision)

Concept IDs: log-argument-evaluation, log-informal-fallacies, log-burden-of-proof, log-charity-principle

What Counts as an Argument

An argument in the logical sense is a set of claims where some (the premises) are offered as reasons for accepting another (the conclusion). Not every piece of discourse is an argument:

• Description: "The report found that the program reduced costs." Not an argument unless a conclusion is drawn.
• Explanation: "The program reduced costs because of economies of scale." Explanatory, not persuasive -- the "because" gives a reason for the fact, not for believing the fact.
• Assertion: "This policy is good." A claim, not an argument.
• Argument: "This policy is good because it reduces costs without harming quality, and no alternative achieves both." Premises offered, conclusion drawn.

The boundary is not always sharp. Many arguments in the wild are compressed or implicit; part of the skill is recognizing an argument when its structure is not marked out.

Premise and Conclusion Markers

Natural language signals that mark the parts of an argument:

Premise markers (the reason-giving side):

• because, since, for, given that, as, in view of the fact that, assuming that

Conclusion markers (the conclusion-drawing side):

• therefore, so, thus, hence, consequently, it follows that, accordingly, we can conclude that

Not every sentence with "because" is an argument, and many real arguments have no markers at all. The markers are helpful but not definitive.

The Standard Form of an Argument

When analyzing or reconstructing an argument, write it in standard form:

Premise 1: ...
Premise 2: ...
Premise 3: ...
Conclusion: ...

With the conclusion clearly labeled, the logical structure becomes visible. Any missing or implicit premise should be made explicit -- bringing out the hidden assumptions is often the most important step in evaluation.

Example. "Smith would make a bad senator. He lies on his tax returns."

Standard form:

• Premise 1: Smith lies on his tax returns.
• (Implicit premise 2: Someone who lies on tax returns would make a bad senator.)
• Conclusion: Smith would make a bad senator.

Making the implicit premise explicit is often where the argument's real weight lies. In this case, the implicit premise is debatable -- does tax dishonesty predict senatorial performance? -- and that is where the argument actually stands or falls.

Charity and Steel-Manning

The principle of charity says: interpret an argument in its strongest reasonable form before evaluating it. Do not attack a misreading. Do not attack a misstatement. Find the best version of the argument the author could have intended, and engage with that.

Steel-manning is the active form of charity: reconstruct the argument as powerfully as possible, possibly better than the author actually made it. Then see if even the steel-manned version fails. If it does, your criticism is strong. If the steel-manned version survives, you owe it a response.

The opposite is straw-manning -- attacking a weak or distorted version of the argument. Straw-manning is easy and produces a feeling of victory; it produces no actual progress.

When charity bottoms out. Charity has limits. If an argument is bad in multiple ways and no reasonable reconstruction saves it, the right move is to say so -- not to invent a different, better argument the author did not make and respond to that one. Charity is interpretation, not substitution.

Deductive Validity vs Inductive Strength

Two very different standards for good argument:

Deductive validity

An argument is deductively valid if its conclusion follows necessarily from its premises -- no possible situation makes the premises true and the conclusion false. Validity is absolute: either the argument is valid or it is not.

An argument is sound if it is valid AND its premises are actually true.

Deductive validity is the standard for mathematical proof, formal derivation, and some legal arguments.

Inductive strength

An argument is inductively strong if its premises make the conclusion likely, even if not certain. Inductive strength is a matter of degree -- arguments can be very strong, moderately strong, weak, or negligible.

Cogency is the inductive counterpart of soundness: a strong argument with true premises.

Scientific inference, everyday reasoning, and most policy argument are inductive. Demanding deductive validity where only inductive strength is available is a common philosophical mistake.

The mismatch error

A common error is judging an inductive argument by deductive standards. "You said X is likely, but I can imagine it being false, so your argument fails." This misunderstands what an inductive argument claims -- it does not claim impossibility, only likelihood.

Burden of Proof

The burden of proof is the obligation to supply evidence for a claim. In any argument, some party is making the claim that requires justification; the other party is, by default, free to withhold agreement until the evidence is supplied.

Default burden-of-proof rules:

• Positive claims have a heavier burden than negative claims. "There is a god" carries more burden than "I do not believe there is a god."
• Extraordinary claims (those that contradict well-established knowledge) have a heavier burden than ordinary claims. Carl Sagan: "Extraordinary claims require extraordinary evidence."
• Claims that invite action (policy proposals, predictions, recommendations) carry the burden of showing their basis.

Shifting the burden is a rhetorical tactic where one side tries to put the burden on the other by framing the question in a way that reverses the default. "Prove God does not exist" shifts the burden from the claimant to the skeptic.

Burden-of-proof disputes are often more productive to address than the underlying substantive disagreement.

Argument Mapping

For complex arguments, a diagram helps. The two main conventions:

Linear form

P1 + P2 → Intermediate conclusion → Final conclusion

Premises combine (via +) to support intermediate conclusions, which combine to support final conclusions.

Tree form

        Final conclusion
          /        \
   Sub-argument   Sub-argument
     /    \         /    \
    P1    P2       P3    P4

Tree diagrams make the hierarchical structure of multi-step arguments visible.

Tools like Rationale, Argdown, and Kialo support computer-aided argument mapping.

Convergent, Linked, and Serial Arguments

Three ways premises can relate in an argument:

Convergent

Each premise independently supports the conclusion. Removing one premise weakens the argument but does not destroy it.

Example. "We should hire Alice because she has excellent credentials, she writes well, and she interviewed brilliantly." Three independent reasons.

Linked

Premises work together; removing one makes the argument collapse.

Example. "All dogs are mammals. All mammals are vertebrates. Therefore all dogs are vertebrates." The premises are linked -- neither alone supports the conclusion.

Serial

One premise supports an intermediate conclusion that support