58

POLITICAL  ECONOMY

equally  a  one-sided  aspect,  enable  the  social
scientist  to  lay  bare  the  ramified  system  of
law  inherent  in  the  economical  functioning
of  communities.
At  this  point,  despite  the  chance  of  confusion, ­
  a  new  idea  must  be  attached  to  the
results  of  our  analysis  of  demand  by  the
marginal  method.  The  term  “  marginal  ”  is
constantly  employed  with  a  meaning  different
from,  though  related  to,  that  ascribed  to  it
above.  It  is  applied  not  merely  to  the
final  increment  of  a  class  of  things  but  also
to  any  particular  thing  in  the  class  which  is
only  just  good  enough  to  be  used.  When  the
second  meaning  is  intended,  it  would  save
misapprehension  if  the  expression  “  marginal
quality  ”  were  used.  Let  me  illustrate  the
distinction.  If  I  pick  twenty  roses  the
twentieth  is  the  marginal  rose,  and  the  addition ­
  made  by  the  twentieth  to  the  satisfaction
derived  by  me  from  the  roses  is  called  the
marginal  utility  of  twenty  roses  to  me  at  the
time.  Now  the  twenty  roses  are  not  equally
perfect.  The  least  perfect  of  the  twenty,  the
one  on  the  margin  of  being  rejected,  is  also
loosely  designated  the  marginal  rose,  or,  as  we
had  better  say,  the  rose  of  marginal  quality.
Similarly,  of  one  hundred  workmen  employed
on  a  job,  any  individual  who  is  only  just