AmMJa?ch,F903.rm-}         Life-History  of  a  Doctrine.  123 
activity  of  nature,  and  they  may  then  see  that  our  mechanical  and 
materialistic  conceptions  of  natural  phenomena  are  like  the  rude 
drawings  of  a  child  as  compared  with  the  paintings  of  Raphael.  We 
have  glimpses  of  such  a  scientific  millenium  in  a  few  nooks  and  cor- 
ners of  physics.  When  that  time  shall  come  the  physicists  and 
chemists  will  in  a  way  be  superfluous.  Everything  will  take  the 
form  of  mathematics.  By  mental  operations  alone  it  will  then  be 
possible  to  solve  such  problems  as  may  remain  to  be  solved.  It  will 
then  no  longer  be  necessary  to  work  with  things — or  rather  with 
those  manifestations  of  energy  which  in  by-gone  ages  (say  the  twen- 
tieth century)  had  been  crudely  interpreted  as  indicating  the  exist- 
ence of  matter.  A  few  models  of  molecules,  of  atoms,  of  corpuscles, 
and,  I  fear  I  must  add,  of  ions  may  then  be  preserved  in  the  archaeo- 
logical institutes  for  the  contemplation  of  mathematical  philoso- 
phers. 
What  I  have  just  said  has  not  been  intended  as  a  criticism  of  any 
tendency.  I  have  had  that  vision  as  others  have.  So,  too,  I  have 
had  visions  of  a  heavenly  kingdom  to  come,  and  I  am  thankful  that 
this  has  been  vouchsafed  to  me.  But  that  heavenly  kingdom  is  far 
away  and  so  is  that  scientific  millenium.  Meanwhile  there  is  work 
to  be  done  here  on  earth  and  with  earthly  things.  If  we  were  all 
angels,  a  good  many  problems  that  now  worry  us  would  be  solved — 
never  to  be  solved  again.  So,  too,  in  that  scientific  millenium  such 
work  as  scientific  men  now  do  will  not  be  called  for.  I  sometimes 
think  that  the  man  with  the  distinctly  mathematical  mind  must 
necessarily  be  unhappy  if  he  applies  himself  to  the  study  of  natural 
phenomena.  The  points  of  contact  between  his  language  and  the 
facts  established  are  relatively  so  few  that  he  must  have  sensations 
like  those  of  a  man  with  large  wealth  in  a  desert  island.  I  once 
knew  a  young  mathematician,  even  then  distinguished,  who  had 
made  something  of  a  study  of  physics.  He  needed  to  add  to  his 
income  and  an  opportunity  offered  itself  to  him  to  coach  some  stu- 
dents of  physics.  He  tried  this  and  had  to  give  it  up.  One  even- 
ing I  found  him  in  great  distress.  He  told  me  that  he  had  been 
trying  to  explain  the  law  of  falling  bodies  to  his  scholars  and  had 
failed  to  make  any  impression  on  them.  He  confessed  that  he  him- 
self had  no  conception  of  the  significance  of  the  law  except  as  it 
appeared  to  him  in  a  mathematical  expression.  He  could  not  think 
ot  a  falling  body  as  such.    The  mathematical  expression 
