I started with a quote from Boas that I modified. In the original, Boas did not write of "humanity"; he wrote of "man." There is an ambiguity here. I suspect that Boas, 50 years later, could have written "man and woman" without changing anything else in the article (or in most of his other published works either, for that matter). He would not have countenanced a substantialization of gender that would make of "man" the only gender to transform its world historically. Man and woman do it equally and together. But there is, in the pre-feminism use of "man," another ambiguity. Boas could have been writing about a singular person (whether male or female, child or adult, etc.) and thus indexing psychological issues that were undoutedly of great interests to him. He could also have been writing about the collectivity of all human beings, from the earliest to the latest of them, here, there and everywhere, that is about humanity in its peculiarities. This is the use I build upon here.