ABSTRACT
Thiswasthebirthoftheprobabilisticformofthekinetictheory;that is,ofstatisticalmechanicsproper(though,asBoltzmannpointsout, 'Clausius,Maxwellandothershavesaidrepeatedlybeforethatthetheoremsofgastheoryhavethecharacterofstatisticaltruths' 89).Theresults wereeminentlyfruitful.ButtheParmenideanparadoxroseagain,andata momentwhentheatomictheorywasviolentlyattackedfromallsidesand especiallybyMachandOstwald;andPoincareremarkedin1893thathe wasscepticalofanyderivationinwhich'reversibilityisfoundinthe premisesandirreversibilityintheconclusion'.90
