Key Assumption Check

This scheme asserts that an unsupported CLAIM in an argument map is an assumption that must be justified. The QUALIFIER is presumably. The DATA for the scheme is an unstated premise (which is incidentally itself an assumption) that implies that CLAIM is presumably a valid assumption.

The critical questions are:

• How confident are you that this assumption is correct? What explains your degree of confidence?

• What circumstances or information might undermine this assumption?

• Could this assumption have been true in the past, but less so now?

The scheme has no WARRANT and hence no BACKING. The only possible rebuttal is an assertion that CLAIM is an invalid assumption.

Notes

Evaluation of this scheme gives just one extension, where the critical questions are acceptable and CLAIM is unacceptable (an invalid assumption). The assumption can only be made valid by "answering" each of the critical questions with an argument that undermines or undercuts it. If all questions are answered, then there is no attack on the inference that CLAIM is a valid assumption, and the scheme evaluates to a single extension with CLAIM skeptically acceptable.

The critical questions under the first bullet point form a coordinative argument. This argument can be defeated by answering either question.