jim.shamlin.com

12 - Argument Analysis

Intuitively, we sense that a good argument is one in which the premises provide good reason for the conclusion. This is delightfully vague, so the author attempts to make it more precise by considering four conditions:

  1. The premises are plausible. Each of the statements as accepted to be true or conceded to be highly probable. Where any premise is false or weak, we reject the argument.
  2. The argument is deductively valid or inductively strong. Ideally, it should be both, but one can carry the other: we may recognize an argument as valid, but weak (which makes us suspicious of its veracity but unable to dismiss it) or invalid but strong (which makes us uncertain it is relevant or reliable, but again unable to dismiss it)
  3. The premises of the argument are independent. That is, we accept that the premise is true based on the information it contains, not because of a rejection of a statement to the contrary.
  4. The premises are relevant to the conclusion. There must be a clear logical connection between each premise and the conclusion - the argument cannot be based on non sequiturs and is weekend by the presence of irrelevant premises.

Four Ways to Attack an Argument

Given these conditions, the author suggests methods for attacking an argument:

  1. Attack the premises (direct). If you can demonstrate that one or more of the premises are false (which means you assume the burden of proof) or implausible (keeping the burden of proof on the author), then the argument fails and the conclusion cannot be supported.
  2. Attack the reasoning (direct). A premise may be plausible in itself, but it may not support the conclusion.
  3. Attack the conclusion (indirect). You can bypass the criteria and the logic by suggesting that the conclusion is false for other reasons. This strategy doesn't explain what is wrong with the argument, but presents a counter-argument to be considered.
  4. Compare the argument to another that is known to be bad (indirect). This, too, avoids considering the premises of logic intrinsic to the argument and attempts to associate it to a bad argument. This is fairly weak, suggesting guilt by association, but is a common tactic when you can't figure out what's wrong with an argument.

As an example, the author presents the argument that "capital punishment is wrong because it is always possible to punish an innocent person by mistake." Her are how those four options can be applied:

  1. Attack the premise: it is not always possible to punish an innocent, as there are some instances in which the evidence is irrefutable (a surveillance camera captured the entire act)
  2. Attack the reasoning: even if mistakes are possible, this does not mean that capital punishment is wrong
  3. Attack the conclusion: punishment is "right" when it is proportionate to the crime, therefore it is not wrong to kill a killer
  4. Compare to a bad argument: it is also possible to punish an innocent person by imprisonment, and it would be absurd to suggest that imprisonment is therefore wrong.

There's much more to be said about capital punishment, as it's an argument that has been made and attacked for millennia without being convincingly won. In essence, don't get hung up on the example, juts notice how each attack is constructed.

Argument Analysis: Checklist

The author provides a checklist that covers most of the "basic parts of critical thinking" - it's worth considering in constructing or attacking any argument.

First, analyze the argument:

Evaluate the argument: