Thus  has  every  kind  of  proof  concurred  to  establish  that  great
fundamental  law  which  is  the  noblest  result  of  our  aggregate
studies  of  nature.  All  the  molecules  of  our  system  gravitate  toward
each  other,  in  proportion  to  their  masses,  and  inversely  to  the
squares  of  their  distances.
Domain  of  the  ^  ^^^^  110*)  ^s  many  do,  confidently  extend  the  ap-
'""■  plication  of  this  law  to  the  entire  universe.      There

can  be  no  objection  to  entertaining  it  analogically  till  we  obtain
some  knowledge  of  the  mechanism  of  the  sidereal  heavens ;  but  we
must  remember  that  we  have  not  yet  that  knowledge,  and  that
we  can  not  promise  ourselves  that  we  ever  shall.  Without  the
phenomena  of  our  own  system,  the  theory  of  its  motions  would  be
only  an  intellectual  exercise  and  sport :  there  can  be  no  positive
science  apart  from  phenomena,  and  of  the  phenomena  of  the  uni-
verse beyond  our  own  system  we  are  not  in  scientific  possession.*
It  must  be  understood  that  I  advocate  simply  a  suspension  of  judg-
meat  where  there  is  no  ground  for  cither  affirmation  or  denial.  I
merely  desire  to  keep  in  view  that  all  our  positive  knowledge  is
relative ;  and,  in  my  dread  of  our  resting  in  notions  of  anything
absolute,  I  would  venture  to  say  that  I  can  conceive  of  such  a  thing

•  *om'  '^T'"  °""'^  here  all  notice  of  such  positive  applications  as  we  are  able  to  make
111  Snleroii  nstn.nomy.  He  t„kes  no  notice  of  the  fact  that  the  motion  of  the  multiple
stars  ...  rlliptical  orbus,  ,,„d  in  accordance  with  Kepler's  law  of  the  velocities,  demon-
strates^th^  existence  of  a  law  of  force,  according  to  the  inverse  square  of  the  listance.
