advantages  or  disadvantages  due  to  it.  (1)
Where  labour  is  very  highly  specialised,  the
effect  of  perpetual  concentration  of  the  mind  on
a  single  operation  is  deadening  to  the  mental
faculties.  We  are  all  aware  that  variety  of
occupation  produces  a  healthy  state  of  mind,
and  that  while  perpetual  practice  of  one  thing
brings  about  a  kind  of  mechanical  perfection,  it
has  a  deteriorating  effect  on  the  faculties  in
general.  The  principal  way  in  which  this  con-
sequence of  the  division  of  labour  acts  on  its
productivity,  perhaps,  is  that  it  counterbalances
to  a  large  extent  the  probability  of  useful  in-
ventions which  we  counted  among  the  results
on  the  other  side  of  the  question.  On  the
other  hand,  it  is  urged  that  work  performed
mechanically  frees  the  mind  and  gives  more
time  for  thought.  (2)  A  more  important  con-
sideration, but  one  which  affects  not  the  labour
of  the  individual  so  much  as  labour  in  the
gross,  is  this — that  the  specialisation  of  labour
of  necessity  involves  the  unsuitability  of  the
average  workman  for  any  kind  of  work  other
than  that  he  has  been  trained  to.  For  example,
suppose  that  a  workman  is  employed  on  some
small  but  delicate  mechanical  operation,  which
he  has  trained  himself  by  long  practice  to  per-
form  with  extraordinary  celerity  and  accuracy.
