﻿214 
  ANIMAL 
  BEHAVIOUR 
  

  

  ing 
  modification. 
  A 
  crab 
  or 
  a 
  crayfish 
  learns 
  in 
  a 
  week 
  or 
  

   two 
  to 
  distinguish 
  infallibly 
  between 
  the 
  right 
  way 
  and 
  the 
  

   wrong 
  way 
  to 
  food 
  and 
  freedom. 
  How 
  far 
  down 
  this 
  capac- 
  

   ity 
  extends 
  we 
  do 
  not 
  know; 
  perhaps 
  it 
  requires 
  a 
  nervous 
  

   system 
  of 
  considerable 
  complexity. 
  If 
  we 
  obey 
  the 
  law 
  of 
  

   parsimony, 
  we 
  are 
  led 
  to 
  the 
  conclusion 
  that 
  the 
  creature 
  

   under 
  sufficient 
  stimulus 
  of 
  reward 
  and 
  " 
  of 
  shortening 
  a 
  

   period 
  of 
  unpleasantness 
  and 
  unrest 
  ", 
  forms 
  a 
  habit 
  without 
  

   ' 
  knowing 
  how 
  ', 
  though 
  probably 
  with 
  high-strung 
  attention 
  

   and 
  delicate 
  quivering 
  sensitiveness, 
  and 
  precise 
  registration 
  

   of 
  sequences 
  of 
  movements 
  ; 
  and 
  that 
  after 
  the 
  trick 
  has 
  been 
  

   learned 
  it 
  trusts 
  itself, 
  as 
  a 
  piano-player 
  does 
  who 
  learns 
  in 
  

   quite 
  a 
  different 
  way. 
  Miss 
  Washburn 
  notes 
  that 
  " 
  an 
  ani- 
  

   mal 
  that 
  has 
  gone 
  astray 
  on 
  the 
  path 
  will 
  often 
  find 
  the 
  way 
  

   back 
  to 
  the 
  starting-point, 
  and 
  from 
  there 
  traverse 
  the 
  whole 
  

   road 
  rapidly 
  and 
  unerringly, 
  apparently 
  in 
  the 
  same 
  way 
  

   that 
  a 
  piano-player 
  who 
  has 
  a 
  piece 
  " 
  at 
  his 
  fingers' 
  ends 
  ", 
  

   but 
  has 
  stumbled 
  in 
  a 
  passage, 
  can 
  go 
  through 
  with 
  entire 
  

   success 
  if 
  he 
  starts 
  over 
  again. 
  As 
  piano-players 
  know, 
  

   in 
  such 
  a 
  case 
  it 
  is 
  much 
  better 
  not 
  to 
  attend 
  to 
  stimuli 
  

   at 
  all, 
  but 
  to 
  think 
  of 
  something 
  else; 
  the 
  movements 
  will 
  

   take 
  care 
  of 
  themselves 
  better 
  if 
  consciousness 
  intervenes 
  as 
  

   little 
  as 
  possible" 
  (1909, 
  p. 
  231). 
  

  

  Many 
  experiments 
  have 
  been 
  made 
  with 
  rats, 
  dogs, 
  cats, 
  

   chicks, 
  and 
  other 
  creatures, 
  which 
  learn 
  in 
  the 
  course 
  of 
  

   time 
  to 
  find 
  their 
  way 
  out 
  of 
  labyrinths 
  and 
  puzzle-boxes. 
  

   After 
  some 
  practice 
  they 
  are 
  left 
  in 
  peace 
  for 
  a 
  few 
  days 
  

   and 
  then 
  replaced 
  in 
  the 
  previous 
  situation. 
  It 
  is 
  observed 
  

   that 
  they 
  make 
  fewer 
  useless 
  movements, 
  that 
  they 
  sometimes 
  

   make 
  none. 
  The 
  question 
  is 
  whether 
  ideas 
  are 
  at 
  work, 
  

   whether 
  the 
  creatures 
  think. 
  Have 
  they 
  remembered 
  images 
  

   of 
  their 
  successful 
  movements, 
  or 
  do 
  they 
  obey 
  the 
  prompt- 
  

  

  