Hertz's principles

Simon Saunders

pp. 123-154

in: Davis Baird, Hughes, Alfred Nordmann (eds), Heinrich Hertz, Berlin, Springer, 1998

Abstract

There are a number of reasons to be interested in Hertz's Principles of Mechanics. The Introduction is a classic in the philosophy of science, and was widely influential. The two Books that follow provide an axiomatization of mechanics in which a priori assumptions (Book 1) are sharply distinguished from the single 'synthetic" postulate (Book 2). The work as a whole defends an alternative to the conventional formalism; the notion of "force" is derived from a more basic theory, based only on kinematic concepts together with the notion of "equations of connection" or constraints. Thereby "painful contradictions' in the conventional framework, as understood by Hertz, "will not have been answered; but our minds, no longer vexed, will cease to ask illegitimate questions' (PM 8). And questions of what exists are answered quite differently: the kinematical equations (and constraints) are supplemented by "hidden masses," in order to account for the appearance of distance forces in the usual theory; in place of fields of force we have a mechanical medium subject only to kinematical laws and the equations of constraint.