 Ernest Nagel’s general treatment of reductionism in chapters 11 and 12 of The Structure of Science (1961) canvassed many different aspects of these perennial debates. Whereas the sections concerning theory reduction have usually been in view (connecting with the reductionist theme of relating domains of knowledge), Nagel also interacted with biological literature addressing claims about parts, wholes, and emergence, thereby addressing the second reductionist theme that has been prominent since Aristotle (see Nagel 1961, 366ff). He highlighted the polysemy of “wholes”, “parts”, and “sums” inherent in claims about success or failure in showing that the whole is just the sum of its parts (pp. 380ff). Additionally Nagel treats the question of evolutionary emergence, i.e., whether genuinely new entities arise in the history of our universe and life on Earth (see Goudge 1961). He dealt with the aforementioned theoretical biologists (e.g., Bertalanffy, Russell, and Woodger) on the topic of hierarchical organization and reduction in living systems, especially as seen in ontogeny (Nagel 1961, pp. 432ff). Nagel’s contemporaries likewise treated reductionist themes, though their work has largely been overlooked (e.g., Morton Beckner’s discussion of “organization” and “levels of analysis” as methodological and explanatory aspects of reduction; Beckner 1959, ch. 9).