In French mechanical treatises of the nineteenth century, Newton’s second law of motion was frequently derived from a relativity principle. The origin of this trend is found in ingenious arguments by Huygens and Laplace, with intermediate contributions by Euler and d’Alembert. The derivations initially relied on Galilean relativity and impulsive forces. After Bélanger’s Cours de mécanique of 1847, they employed continuous forces and a stronger relativity with respect to any commonly impressed motion. The name “principle of relative motions” and the (...) very idea of using this principle as a constructive tool were born in this context. The consequences of Poincaré’s and Einstein’s awareness of this approach are analyzed. Lastly, the legitimacy and significance of a relativity-based derivation of Newton’s second law are briefly discussed in a more philosophical vein. (shrink)

This paper argues that a debate between Toland and Clarke is the intellectual context to help understand the motive behind the critic and the significance of Berkeley's response to the critic in PHK 60-66. These, in turn, are responding to Boyle's adaptation of a neglected design argument by Cicero. The paper shows that there is an intimate connection between these claims of natural science and a once famous design argument. In particular, that in the early modern period the connection between (...) the scientific revolution and a certain commitment to final causes, and god's design, is more than merely contingent. The details of PHK 60-66 support the idea that the critic is responding to concerns that by echoing features of Toland's argument Berkeley undermines the Newtonian edifice Clarke has constructed. (shrink)