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POLITICAL  ECONOMY

what  would  be  the  payment  for  the  marginal
thing  of  the  class  (which,  to  distinguish  it
from  “  differential  rent,”  can  be  called  a
“scarcity  rent”).  Of  course,  in  a  sense  socalled
  scarcity  rent  is  a  payment  for  differential
advantages,  since  persons  who  possess  a  rare
thing  enjoy  differential  advantages  over  those
who  have  not  got  it  and  cannot  get  it.  But
in  what  follows,  for  the  sake  of  convenience
of  terminology,  I  shall  use  “  differential
advantage  ”  with  the  meaning  intended
when  differential  rent  is  distinguished  from
scarcity  rent.
At  first,  so  as  to  limit  the  data  to  which
attention  must  be  given,  we  shall  deal
merely  with  the  economic  rent  of  land.
We  shall  make  a  start  with  the  simplest
conditions  conceivable.  Let  us  imagine  that
the  same  amount  of  capital  and  labour  is
applied  in  cultivating  any  one  acre  of  land
in  use  in  a  country  as  any  other.  The
fertility  of  a  plot  of  ground  has  no  influence
over  the  degree  of  its  cultivation,  we  premise  ;
and  we  assume,  further,  that  the  situation  of
a  farm  is  a  thing  of  no  importance,  and  that
consequently,  in  the  matter  of  the  choice
of  land,  it  is  fertility  alone  that  counts.
Coming  next  to  detail,  let  us  suppose  that  the