People rely extensively on inference as a source of information, and sometimes they confuse inference with observation. Specifically, inferred information is sometimes mistaken for observed information. Such confusion of inference with observation can be problematic, especially if the inferred information is erroneous. One factor that might affect the probability of mistaking inference for observation is the degree of consistency between inferred information and subsequently encountered information. The present research was designed to test this possibility. In three experiments subjects made inferences on the basis of presented information, and then were given additional information that was varied in consistency with the information they had inferred. Finally, subjects were tested for accuracy in discriminating the source (inference vs. observation) of the inferred information. As expected, accuracy was lower when subsequently presented information was relatively consistent with inferred information than when it was relatively inconsistent with inferred information. This effect did not vary with delay between making an inference and attempting to discriminate information source. It is concluded that consistency of inferred information with subsequently encountered information can affect the probability of mistaking inference for observation, with the probability of error increasing as consistency increases.