A cast of thousands: Coauthorship and subauthorship collaboration in the 20th century as manifested in the scholarly journal literature of psychology and philosophy

We chronicle the use of acknowledgments in 20th-century scholarship by analyzing and classifying more than 4,500 specimens covering a 100-year period. Our results show that the intensity of acknowledgment varies by discipline, reflecting differences in prevailing sociocognitive structures and work practices. We demonstrate that the acknowledgment has gradually established itself as a constitutive element of academic writing, one that provides a revealing insight into the nature and extent of subauthorship collaboration. Complementary data on rates of coauthorship are also presented to highlight the growing importance of collaboration and the increasing division of labor in contemporary research and scholarship.