The evidence concerning racial differences in intelligence comes from observation of naturally occurring events where experimental controls are lacking, samples are biased, and replication is often impossible. In this messy situation Jensen has considered the large body of evidence as a whole, attempting to resolve inconsistencies, to discount questionable data, and to discern a meaningful pattern within the jumble of noise. Professor Flynn, on the other hand, has selected from the mass of untrustworthy data those lines of evidence that are least consistent with the overall pattern that Jensen has identified. This is a valuable service, since, to maintain the credibility of his conclusions, Jensen must attempt to deal with such inconsistencies, either by discrediting the observations or by reinterpreting them in a manner consistent with the main body of evidence. Flynn goes too far, however, in suggesting that these inconsistent observations overturn, or even raise serious doubts about, Jensen’s conclusions. To accomplish this he must evaluate the inconsistent observations, not in isolation, but alongside the other main lines of evidence, as Jensen has done, applying the same scientific standards to all.