ABSTRACT
R. F. Skinner has provided a detailed analysis of the limited resources available to the community for training its members thus to "know themselves," and he has described the inescapable inadequacies of the resulting knowledge. One implication of Skinner's analysis is that many of the self-descriptive statements that appear to be exclusively under the discriminative control of private stimulation may remain under the control of the same public events. A descriptive statement, a verbal response that is under the discriminative control of some portion of the environment, is classified as a "tact". Attitude statements in particular have the properties of tacts of the reinforcing effects of a stimulus situation on the individual. A communicator is credible to the extent that his communication is discriminated as a set of tacts, and his credibility is vitited to the extent that he appears to be manding in the form of disguised tacts.
