Passage Summary: An art historian thinks older painters were better because their work was flatter. A critic says the historian is wrong because flatness doesn't actually prove how good a painter is.

Conclusion: The art historian's claim that fifteenth-century painters were more skilled than sixteenth-century painters is incorrect.

Reasoning: The critic argues that the historian's evidence—the degree of two-dimensionality in the paintings—is actually irrelevant to determining a painter's level of mastery.

Analysis: This argument exhibits a classic 'absence of evidence' flaw. The critic correctly points out that the historian's evidence is irrelevant, but then oversteps by concluding that the historian's conclusion must therefore be false. In logic, just because you haven't proven a claim doesn't mean the claim is automatically wrong. Look for an answer choice that describes this mistake of treating the failure to prove a claim as a proof of its negation.