andanothertohaveaddedtothatdexterityanacquiredscienceofwherehecanoffend，orbeoffendedbyhisadversary，ineverypossiblepostureorguard：theabilityoftheformerwouldbetotheabilityofthelatter，asprudencetosapience；bothuseful，butthelatterinfallible。Buttheythat，trustingonlytotheauthorityofbooks，followtheblindblindly，arelikehimthat，trustingtothefalserulesofamasteroffence，venturespresumptuouslyuponanadversarythateitherkillsordisgraceshim。
Thesignsofsciencearesomecertainandinfallible；some，uncertain。Certain，whenhethatpretendeththescienceofanythingcanteachthesame；thatistosay，demonstratethetruththereofperspicuouslytoanother：uncertain，whenonlysomeparticulareventsanswertohispretence，anduponmanyoccasionsprovesoashesaystheymust。Signsofprudencearealluncertain；becausetoobservebyexperience，andrememberallcircumstancesthatmayalterthesuccess，isimpossible。Butinanybusiness，whereofamanhasnotinfalliblesciencetoproceedby，toforsakehisownnaturaljudgment，andbeguidedbygeneralsentencesreadinauthors，andsubjecttomanyexceptions，isasignoffolly，andgenerallyscornedbythenameofpedantry。AndevenofthosementhemselvesthatincouncilsoftheCommonwealthlovetoshowtheirreadingofpoliticsandhistory，veryfewdoitintheirdomesticaffairswheretheirparticularinterestisconcerned，havingprudenceenoughfortheirprivateaffairs；butinpublictheystudymorethereputationoftheirownwitthanthesuccessofanother’sbusiness。
OFTHEINTERIORBEGINNINGSOFVOLUNTARYMOTIONS，COMMONLYCALLEDTHEPASSIONS；
ANDTHESPEECHESBYWHICHTHEYAREEXPRESSED
THEREbeinanimalstwosortsofmotionspeculiartothem：Onecalledvital，beguningeneration，andcontinuedwithoutinterruptionthroughtheirwholelife；suchasarethecourseoftheblood，thepulse，thebreathing，theconcoction，nutrition，excretion，etc。；towhichmotionsthereneedsnohelpofimagination：theotherisanimalmotion，otherwisecalledvoluntarymotion；astogo，tospeak，tomoveanyofourlimbs，insuchmannerasisfirstfanciedinourminds。Thatsenseismotionintheorgansandinteriorpartsofman’sbody，causedbytheactionofthethingswesee，hear，etc。，andthatfancyisbuttherelicsofthesamemotion，remainingaftersense，hasbeenalreadysaidinthefirstandsecondchapters。Andbecausegoing，speaking，andthelikevoluntarymotionsdependalwaysuponaprecedentthoughtofwhither，whichway，andwhat，itisevidentthattheimaginationisthefirstinternalbeginningofallvoluntarymotion。Andalthoughunstudiedmendonotconceiveanymotionatalltobethere，wherethethingmovedisinvisible，orthespaceitismovedinis，fortheshortnessofit，insensible；