When research on learned control of the viscera first began to appear in the literature, the Zeitgeist, reflecting centuries of prejudice against the voluntary status of visceral responses, demanded evidence that the reported autonomic changes were not an artifact of “true voluntary” somatomotor activity. Since the characteristics of such true voluntary responses have not been made explicit, the difficulty of proving that cardiovascular responses are members of this class is insurmountable. Nevertheless a response was and is still often thought to be voluntary only if it is not “mediated” by some other response (Katkin and Murray 1968). Although it is doubtful that the issue of mediation is resolvable at an empirical level (Brener 1970a), experiments involving curarized rats were initiated to bolster the case for operant and voluntary visceral phenomena. Thus Miller and his colleagues (Miller et al. 1970) provide the following rationale for the long series of experiments emanating from his laboratory: “In order to prevent the rats from affecting their heart rates indirectly by changes in breathing and muscular activity, the skeletal muscles were completely paralyzed by curare and the rats were maintained on artificial respiration.” (Miller et al. 1970, p. 1-4) That the curare literature served to establish the scientific respectability of these phenomena contains a double irony. In the first instance, the rationale provided for performing these experiments is open to a 252number of substantial criticisms. Secondly, the magnitude and reliability of the phenomena reported in the initial publications of DiCara and Miller (Miller and Dworkin, Chapter 16) are open to question.