This paper presents a mathematical model of knowledge accumulation in early modern science, using the *Sphaera* corpus—a collection of over 350 astronomy textbooks from European universities (1472-1650). The model analyzes the spread of knowledge units (semantic text-parts) between editions using SI and Bass models, considering factors like transmission rate and external influence. The results reveal a strong dependence of knowledge accumulation on the institutional and economic context of scientific production, particularly the economic constraints faced by early modern printers and publishers.
