rejected　by　the　present。
  The　objection　likely　to　be　made　to　this　argument　would　probably　take
  some　such　form　as　the　following。　There　is　no　greater　assumption　of
  infallibility　in　forbidding　the　propagation　of　error；　than　in　any
  other　thing　which　is　done　by　public　authority　on　its　own　judgment
  and　responsibility。　Judgment　is　given　to　men　that　they　may　use　it。
  Because　it　may　be　used　erroneously；　are　men　to　be　told　that　they　ought
  not　to　use　it　at　all？　To　prohibit　what　they　think　pernicious；　is　not
  claiming　exemption　from　error；　but　fulfilling　the　duty　incumbent　on
  them；　although　fallible；　of　acting　on　their　conscientious
  conviction。　If　we　were　never　to　act　on　our　opinions；　because　those
  opinions　may　be　wrong；　we　should　leave　all　our　interests　uncared
  for；　and　all　our　duties　unperformed。　An　objection　which　applies　to　all
  conduct　can　be　no　valid　objection　to　any　conduct　in　particular。　It
  is　the　duty　of　governments；　and　of　individuals；　to　form　the　truest
  opinions　they　can；　to　form　them　carefully；　and　never　impose　them
  upon　others　unless　they　are　quite　sure　of　being　right。　But　when　they
  are　sure　（such　reasoners　may　say）；　it　is　not　conscientiousness　but
  cowardice　to　shrink　from　acting　on　their　opinions；　and　allow　doctrines
  which　they　honestly　think　dangerous　to　the　welfare　of　mankind；
  either　in　this　life　or　in　another；　to　be　scattered　abroad　without
  restraint；　because　other　people；　in　less　enlightened　times；　have
  persecuted　opinions　now　believed　to　be　true。　Let　us　take　care；　it
  may　be　said；　not　to　make　the　same　mistake：　but　governments　and　nations
  have　made　mistakes　in　other　things；　which　are　not　denied　to　be　fit
  subjects　for　the　exercise　of　authority：　they　have　laid　on　bad　taxes；
  made　unjust　wars。　Ought　we　therefore　to　lay　on　no　taxes；　and；　under
  whatever　provocation；　make　no　wars？　Men；　and　governments；　must　act
  to　the　best　of　their　ability。　There　is　no　such　thing　as　absolute
  certainty；　but　there　is　assurance　sufficient　for　the　purposes　of　human
  life。　We　may；　and　must；　assume　our　opinion　to　be　true　for　the　guidance
  of　our　own　conduct：　and　it　is　assuming　no　more　when　we　forbid　bad
  men　to　pervert　society　by　the　propagation　of　opinions　which　we
  regard　as　false　and　pernicious。
  I　answer；　that　it　is　assuming　very　much　more。　There　is　the
  greatest　difference　between　presuming　an　opinion　to　be　true；
  because；　with　every　opportunity　for　contesting　it；　it　has　not　been
  refuted；　and　assuming　its　truth　for　the　purpose　of　not　permitting
  its　refutation。　Complete　liberty　of　contradicting　and　disproving　our
  opinion　is　the　very　condition　which　justifies　us　in　assuming　its　truth
  for　purposes　of　action；　and　on　no　other　terms　can　a　being　with　human
  faculties　have　any　rational　assurance　of　being　right。
  When　we　consider　either　the　history　of　opinion；　or　the　ordinary
  conduct　of　human　life；　to　what　is　it　to　be　ascribed　that　the　one　and
  the　other　are　no　worse　than　they　are？　Not　certainly　to　the　inherent
  force　of　the　human　understanding；　for；　on　any　matter　not　self…evident；
  there　are　ninety…nine　persons　totally　incapable　of　judging　of　it　for
  one　who　is　capable；　and　the　capacity　of　the　hundredth　person　is　only
  comparative；　for　the　majority　of　the　eminent　men　of　every　past
  generation　held　many　opinions　now　known　to　be　erroneous；　and　did　or
  approved　numerous　things　which　no　one　will　now　justify。　Why　is　it；
  then；　that　there　is　on　the　whole　a　preponderance　among　mankind　of
  rational　opinions　and　rational　conduct？　If　there　really　is　this
  preponderance…　which　there　must　be　unless　human　affairs　are；　and　have
  always　been；　in　an　almost　desperate　state…　it　is　owing　to　a　quality
  of　the　human　mind；　the　source　of　everything　respectable　in　man
  either　as　an　intellectual　or　as　a　moral　being；　namely；　that　his　errors
  are　corrigible。　He　is　capable　of　rectifying　his　mistakes；　by
  discussion　and　experience。　Not　by　experience　alone。　There　must　be
  discussion；　to　show　how　experience　is　to　be　interpreted。　Wrong
  opinions　and　practices　gradually　yield　to　fact　and　argument；　but　facts
  and　arguments；　to　produce　any　effect　on　the　mind；　must　be　brought
  before　it。　Very　few　facts　are　able　to　tell　their　own　story；　without
  comments　to　bring　out　their　meaning。　The　whole　strength　and　value；
  then；　of　human　judgment；　depending　on　the　one　property；　that　it　can　be
  set　right　when　it　is　wrong；　reliance　can　be　placed　on　it　only　when　the
  means　of　setting　it　right　are　kept　constantly　at　hand。　In　the　case
  of　any　person　whose　judgment　is　really　deserving　of　confidence；　how
  has　it　become　so？　Because　he　has　kept　his　mind　open　to　criticism　of
  his　opinions　and　conduct。　Because　it　has　been　his　practice　to　listen
  to　all　that　could　be　said　against　him；　to　profit　by　as　much　of　it　as
  was　just；　and　expound　to　himself；　and　upon　occasion　to　others；　the
  fallacy　of　what　was　fallacious。　Because　he　has　felt；　that　the　only　way
  in　which　a　human　being　can　make　some　approach　to　knowing　the　whole
  of　a　subject；　is　by　hearing　what　can　be　said　about　it　by　persons　of
  every　variety　of　opinion；　and　studying　all　modes　in　which　it　can　be
  looked　at　by　every　character　of　mind。　No　wise　man　ever　acquired　his
  wisdom　in　any　mode　but　this；　nor　is　it　in　the　nature　of　human
  intellect　to　become　wise　in　any　other　manner。　The　steady　habit　of
  correcting　and　completing　his　own　opinion　by　collating　it　with　those
  of　others；　so　far　from　causing　doubt　and　hesitation　in　carrying　it
  into　practice；　is　the　only　stable　foundation　for　a　just　reliance　on
  it：　for；　being　cognisant　of　all　that　can；　at　least　obviously；　be
  said　against　him；　and　having　taken　up　his　position　against　all
  gainsayers…　knowing　that　he　has　sought　for　objections　and
  difficulties；　instead　of　avoiding　them；　and　has　shut　out　no　light
  which　can　be　thrown　upon　the　subject　from　any　quarter…　he　has　a　right
  to　think　his　judgment　better　than　that　of　any　person；　or　any
  multitude；　who　have　not　gone　through　a　similar　process。
  It　is　not　too　much　to　require　that　what　the　wisest　of　mankind；　those
  who　are　best　entitled　to　trust　their　own　judgment；　find　necessary　to
  warrant　their　relying　on　it；　should　be　submitted　to　by　that
  miscellaneous　collection　of　a　few　wise　and　many　foolish　individuals；
  called　the　public。　The　most　intolerant　of　churches；　the　Roman　Catholic
  Church；　even　at　the　canonisation　of　a　saint；　admits；　and　listens
  patiently　to；　a　〃devil's　advocate。〃　The　holiest　of　men；　it　appears；
  cannot　be　admitted　to　posthumous　honours；　until　all　that　the　devil
  could　say　against　him　is　known　and　weighed。　If　even　the　Newtonian
  philosophy　were　not　permitted　to　be　questioned；　mankind　could　not　feel
  as　complete　assurance　of　its　truth　as　they　now　do。　The　beliefs　which
  we　have　most　warrant　for　have　no　safeguard　to　rest　on；　but　a
  standing　invitation　to　the　whole　world　to　prove　them　unfounded。　If　the
  challenge　is　not　accepted；　or　is　accepted　and　the　attempt　fails；　we
  are　far　enough　from　certainty　still；　but　we　have　done　the　best　that
  the　existing　state　of　human　reason　admits　of；　we　have　neglected
  nothing　that　could　give　the　truth　a　chance　of　reaching　us：　if　the
  lists　are　kept　open；　we　may　hope　that　if　there　be　a　better　truth；　it
  will　be　found　when　the　human　mind　is　capable　of　receiving　it；　and　in
  the　meantime　we　may　rely　on　having　attained　such　approach　to　truth
  as　is　possible　in　our　own　day。　This　is　the　amount　of　certainty
  attainable　by　a　fallible　being；　and　this　the　sole　way　of　attaining　it。
  Strange　it　is；　that　men　should　admit　the　validity　of　the　arguments
  for　free　discussion；　but　object　to　their　being　〃pushed　to　an　extreme〃；
  not　seeing　that　unless　the　reasons　are　good　for　an　extreme　case；
  they　are　not　good　for　any　case。　Strange　that　they　should　imagine
  that　they　are　not　assuming　infallibility；　when　they　acknowledge　that
  there　should　be　free　discussion　on　all　subjects　which　can　possibly
  be　doubtful；　but　think　that　some　particular　principle　or　doctrine
  should　be　forbidden　to　be　questioned　because　it　is　so　certain；　that
  is；　because　they　are　certain　that　it　is　certain。　To　call　any
  proposition　certain；　while　there　is　any　one　who　would　deny　its
  certainty　if　permitted；　but　who　is　not　permitted；　is　to　assume　that　we
  ourselves；　and　those　who　agree　with　us；　are　the　judges　of　certainty；
  and　judges　without　hearing　the　other　side。
  In　the　present　age…　which　has　been　described　as　〃destitute　of
  faith；　but　terrified　at　scepticism〃…　in　which　people　feel　sure；　not
  so　much　that　their　opinions　are　true；　as　that　they　should　not　know
  what　to　do　without　them…　the　claims　of　an　opinion　to　be　protected
  from　public　attack　are　rested　not　so　much　on　its　truth；　as　on　its
  importance　to　society。　There　are；　it　is　alleged；　certain　beliefs　so
  useful；　not　to　say　indispensable；　to　well…being　that　it　is　as　much　the