The  two  remaining  ideas  which  Dr.  Reid  thinks  cannot
be  traced  back,  either  to  sensation  or  reflection,  are  those
which  we  have  of  substance,  and  of  personal  identity.  His
views  in  reference  to  the  first,  are  thus  expressed  by  him—
"  It  were  to  be  wished  that  Mr.  Locke,  who  inquired  so
accurately,  and  so  laudably  into  the  origin,  certainty,  and
extent  of  human  knowledge,  had  turned  his  attention  more
particularly  to  the  origin  of  these  two  opinions,  which  he
firmly  believed;  to  wit,  that  sensible  qualities  must  have  a
subject,  which  we  call  body,  and  that  thought  must  have  a
subject,  which  we  call  mind.  A  due  attention  to  these  two
opinioins,  which  govern  the  belief  of  all  men,  even  of  scep-
tics, in  the  practice  of  life,  would  probably  have  led  him  to
perceive,  that  sensation  and  consciousness,  are  not  the  only
sources  of  human  knowledge,  and  that  there  are  principles  of
belief  in  human  nature,  of  which  we  can  give  no  account,  but
that  they  necessarily  result  from  the  constitution  of  our  facul-
ties; and  that  if  it  were  in  our  power  to  throw  oiF  their  in-
fluence upon  our  conduct  and  practice,  we  could  neither
speak  nor  act  like  reasonable  men.  We  cannot  give  a  rea-
son, why  we  believe  even  our  sensations  to  be  real  and  not
fallacious;  why  we  believe  what  we  are  conscious  of;  why  we
trust  any  of  our  natural  faculties,  &c."  Here  we  were  led  to
conclude,  in  the  first  part  of  this  paragraph,  that  we  should
meet  with  a  suflicient  argument  to  show,  that  sensation  and
consciousness,  are  not  the  only  sources  of  human  knowledge;
but  to  our  disappointment,  we  find  it  only  asserted,  what  no
one  denies,  that  there  are  principles  of  belief  in  human  na-
ture, of  which  we  can  give  no  other  account,  but  that  they
necessarily  result  from  the  constitution  of  our  faculties.
