The English Galileo: Thomas Harriot and the Force of Shared Knowledge in Early Modern Mechanics

I discuss the work of the English mathematician and philosopher Thomas Harriot (1560–1621), analyzing especially his work on projectile motion, and comparing it to that of his contemporary Galileo Galilei (1564–1642). I argue that although their work on projectile motion was carried out independently and displays both similarities and differences, it shows that they focused on common challenging objects of study that embodied what I term “points of contact” between preclassical and classical mechanics. I also argue that their shared knowledge defined the space of possible solutions to the problem of projectile motion, although the inferential pathways they followed through their shared knowledge proceeded in exactly opposite directions. I conclude that their work suggests that the lines of development in early modern mechanics converged in such a way that the long-term development of science was largely unaffected by the peculiarities in an individual scientist’s work.