Work on functional neuroimaging of cognition falls into two categories. The first aims at localizing specific cognitive subsystems in specific brain regions. In this research, the cognitive subsystems in question need to be defined independently of the neuroimaging data because the interpretation of the data requires such definition; so functional neuroimaging is informed by cognitive theories rather than informing them. The second category uses neuroimaging data to test cognitive theories. As cognitive theories are expressed in cognitive terms, such theories have to be embellished by explicit proposals about relationships between cognition and the brain if they are to become capable of generating predictions about the results of experiments that use functional neuroimaging. Whether functional neuroimaging can succeed in informing a cognitive theory depends critically upon the plausibility of such supplementary proposals. It is also critical to avoid the "consistency fallacy." When neuroimaging data from an experiment are consistent with predictions from a particular cognitive theory, this cannot be offered as evidence in support of that theory unless it can be shown that there were possible other outcomes of the experiment that are inconsistent with the theory-outcomes that would have falsified predictions from the theory had they been obtained.