In a report published after the article by Dr. Sato et al. was submitted, we described five subtypes of mania identified by grade-of-membership analysis (3). Type 1 is a nonpsychotic, relatively mild form of mania that corresponds to Kraepelin’s "hypomania" and to subgroup 1 in the current report. Type 2 is a severe form of classical mania, with high levels of psychomotor activity, irritability, and psychosis, which corresponds to Kraepelin’s "acute mania." Type 3 is a very delusional form of mania with relatively less severe classical manic symptoms that corresponds to Kraepelin’s delusional mania and perhaps to subgroup 3 in the report by Dr. Sato et al. Type 4 is a severe form of mania with high levels of dysphoric symptoms and the complete absence of grandiosity or euphoria that corresponds to Kraepelin’s anxious or depressive mania. Type 5 is an overall less severe form of dysphoric mania than type 4, with moderate degrees of depressive mood symptoms alternating or coexisting with grandiosity, humor, sexuality, and psychomotor acceleration. In the study by Dr. Sato et al., subgroup 4 seems to comprise patients similar to types 4 and 5 in our grade-of-membership analysis. Again, the similarities between the analysis by Dr. Sato et al. and our analysis are more impressive than any differences. Both groups agree that clinical care and research studies of manic patients may benefit from serious attention to the "rediscovered" heterogeneity of clinical subtypes.