In philosophical anthropology, ... where the subject is man in his wholeness, the investigator cannot content himself, as in anthropology as an individual science, with considering man as another part of nature and with ignoring the fact that he, the investigator, is himself a man and experiences this humanity in his inner experience in a way that he simply cannot experience any part of nature.
Martin Buber, S. N. Eisenstadt (1992). “On Intersubjectivity and Cultural Creativity”, p.34, University of Chicago Press