As  the  color  is  an  attribute  of  a  leaf,  so  a  leaf  is  an  attri-
bute of  a  tree,  a  tree  an  attribute  of  the  earth,  the  earth
an  attribute  of  the  universe.  The  universe  is  the  sub-
stsance,  substance  in  general,  and  all  other  substances  are
but  its  attributes.  And  this  world-substance  reveals  the
fact  that  the  nature  of  things,  the  "thing  itself"  as  dis-
tinguished from  its  manifestations,  is  only  a  concept  of  the
mind.
In  its  universal  search  from  the  attribute  to  the
substance,  from  the  relative  to  the  absolute,  from
the  appearance  of  things  to  the  true  things,  the  mind
finally  arrives  at  the  understanding  that  the  substance
is  nothing  but  a  sum  of  attributes  collected  by  brain
activity,  and  that  the  mind  itself,  or  reason,  is  a  sub-
stantial being  which  creates  abstract  mental  units  out
of  a  multitude  of  sense  perceptions  and  conceives  of
the  universe  as  an  absolute  whole,  as  an  independent
"thing  itself,"  by  adding  all  its  transient  manifesta-
tions. In  turning  away  full  ot  dissatisfaction  from
attributes,  searching  restlessly  after  the  substance,
throwing  aside  phenomena,  and  forever  groping  for
truth,  for  the  nature  of  things,  for  the  "thing  itself,"
and  in  finally  realizing  that  this  substantial  truth  is
merely  the  sum  of  all  socalled  untruths,  the  totality  of
all  phenomena,  the  mind  proves  itself  to  be  the  creator
of  the  abstract  concept  of  substance.     But  it  did  not


86  THE    NATURE    OF    HUMAN    BRAIN    WORK

create  this  concept  out  of  nothing.  On  the  contrary,
it  generated  the  concept  of  a  world  substance  out  of
attributes,  it  derived  truth  out  of  manifestations  of  things.
