However, this study was reviewed in an editorial in Nature, which recommended a degree of caution, stating "the critique leaves the majority of Gould's work unscathed," and noted that "because they couldn't measure all the skulls, they do not know whether the average cranial capacities that Morton reported represent his sample accurately."[19] The journal stated that Gould's opposition to racism may have biased his interpretation of Morton's data, but also noted that "Lewis and his colleagues have their own motivations. Several in the group have an association with the University of Pennsylvania, and have an interest in seeing the valuable but understudied skull collection freed from the stigma of bias" and did not accept Gould's theory "that the scientific method is inevitably tainted by bias."[19]