IMG89

Ernst Mach

tcachcrs until aftcr thc fali of that rcgimc in 1893. On thc other hand stimulated by Mach’s Dortmund speech, thc books werc widcly intro-duced into German sccondary schools. Aftcr 1893 Machs tcxtbooks i_n both Germany and Austria werc frequently reprinted and rcvised. The varicty of preparations rcquircd for difTerent types of sccondary schools and often listed under dilTcrcnt titles or under thc rcviscr’s namc, has madę it impossiblc to pin down all the difTerent cditions of “Machs" 1886 work, but twenty cditions havc becn traccd, dating from 1886 to 1919.

Machs 1891 tcxtbook had 372 pages of which 203 were by Mach himsclf, with chapters on chcmistry and astronomy by Machs assistant, Gustav Jaumann, and a Mr. C. Brunner. The basie difTcrcnce bctwccn thc 1886 and 1891 tcxtbooks was that thc first was uscd for lowcr classes in sccondary schools and thc other for upper elasses. The lattcr book, too, had difliculties recciving permission for usc in Austrian schools. Both books camc to be published in increasingly truncatcd and revised forms during thc ncxt three dccadcs. The 1891 book went through fourtcen editions bctwccn 1891 and 1917. Ferdinand Harbordt and Max Fischer reworked both books for German schools in 1893 and werc rcsponsible for most of thc morę radical revisions.

The important qucstions arc: first, to what cxtcnt werc Machs phenomenalism and philosophy of science represented in thcsc tcxt-books? And second, which important physicists or philosophers werc significantly influcnccd by Mach’s ideas as givcn in them^?

In answer to thc first qucry, here are somc quotations from his 1891 textbook and from an 1894 vcrsion of it:

The essence of cvcrything which we perccive through thc senses (colors, tones . . . etc.) we cali thc sense world or naturę.³⁵

Changes in thc qua!itics of matter which are always represented by par-ticular conncctd conditions, we cali appcaranccs (Erschetnungen).^3ł5

Physics (in the wider sense) is thc science of the simpler appcaranccs of inorganic naturę.³⁷

Mach was vcry discreet in his treatment of atoms and molecules.

The relations bctwccn beat and work becomc morę vivid if one thinks of bodics as consisting of ultimatc parts (molecules and atoms) and thinks of all physical proccsscs as mcchanical cvcnts. One should not forget, how-cvcr, that thcsc representations are hypothcscs.⁸⁸

In short, Machs phenomenalism was well represented in his tcxt-books but his philosophy of science only modcratcly so. His criticisms of Newton** idcas ^{sccm lo} have bccn omitted altogcthcr.

In answer to thc sccond qucry, one can safcly speeulate that many wcll-known physicists werc cxposcd to Mach’s phenomenalism and physical idcas during their school days. Albert Einstein, Werner Hci-senberg, Erwin Schrodingcr, Philipp Frank, and most members of the “Vicnna Circle" werc in sccondary schools in Germany and Austria during thc period in which Mach’s tcxtbooks werc available for usc in physics elasses, and virtually all havc tesli fi cd to thc pcrvasivcness of Mach’s influence during their school days. But it is not elear to what cxtcnt Mach’s textbooks contributcd to that pcrvasivcncss; nor is it cvidcnt which, if any, particular scicntists or philosophers werc philo-sophically ‘‘seduccd" by them. Nonetheless, Mach's textbooks werc widcly distributed in Central Europę and presumably did influence a number of intelligcnt rninds, whether his name was remembered as thc author of thosc books or not. Einstein at least hinted at that influence when he wrotc in 1916: “I evcn belicvc, that thosc who con-sider thcmselves opponents of Mach, scarccly know how much they have taken from his way of looking at things, so to say along with their mothcr’s rnilk.

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