﻿MAR. 
  19, 
  1922 
  troland: 
  psychophysics 
  the 
  key 
  of 
  physics, 
  etc. 
  143 
  

  

  physiological 
  acoustics 
  we 
  find 
  the 
  most 
  eminent 
  physicist 
  of 
  the 
  

   nineteenth 
  century 
  explicitly 
  treating 
  both 
  color 
  and 
  tone 
  as 
  physiolog- 
  

   ical 
  or 
  psychological 
  entities. 
  

  

  Up 
  to 
  the 
  advent 
  of 
  the 
  theory 
  of 
  relativity 
  (in 
  the 
  twentieth 
  

   century) 
  it 
  appeared 
  that 
  this 
  process 
  of 
  eliminating 
  the 
  qualitative 
  

   constituents 
  of 
  external 
  experience 
  from 
  the 
  domain 
  of 
  physics 
  still 
  

   left 
  within 
  this 
  latter 
  domain 
  three 
  distinctive 
  factors: 
  those 
  of 
  space, 
  

   mass, 
  and 
  time. 
  The 
  physicist 
  of 
  this 
  period 
  was 
  painstakingly 
  

   construing 
  all 
  of 
  his 
  data 
  and 
  theories 
  in 
  terms 
  of 
  the 
  centimeter, 
  

   the 
  gram 
  and 
  the 
  second. 
  These 
  were 
  regarded 
  as 
  being 
  the 
  ultimate 
  

   physical 
  dimensions, 
  out 
  of 
  which 
  all 
  other 
  physical 
  conceptions 
  

   m.ust 
  be 
  synthesized. 
  It 
  is 
  true 
  that 
  the 
  developing 
  theory 
  of 
  elec- 
  

   tricity 
  apparently 
  demanded 
  two 
  other 
  dimensions: 
  those 
  of 
  di- 
  

   electric 
  capacity 
  and 
  of 
  magnetic 
  permeability, 
  respectively, 
  but 
  

   these 
  latter 
  conceptions 
  attached 
  more 
  to 
  the 
  hypotheses 
  of 
  physics 
  

   than 
  to 
  its 
  actual 
  measurements. 
  Now 
  from 
  the 
  point 
  of 
  view 
  of 
  

   psychology 
  or 
  the 
  analysis 
  of 
  immediate 
  experience, 
  space, 
  mass, 
  and 
  

   time 
  are 
  radically 
  different 
  categories. 
  Only 
  mass 
  can 
  properly 
  be 
  

   regarded 
  as 
  being 
  interpretable 
  as 
  a 
  quality 
  of 
  experience. 
  As 
  such 
  

   it 
  is 
  clearly 
  identifiable 
  with 
  sensations 
  or 
  experiences 
  derived 
  from 
  

   the 
  so-called 
  proprioceptors, 
  or 
  the 
  sense 
  organs 
  of 
  the 
  motor 
  mechan- 
  

   isms 
  of 
  the 
  body, 
  including 
  not 
  only 
  the 
  muscles 
  but 
  the 
  tendons 
  and 
  

   the 
  joints. 
  It 
  is 
  probable, 
  however, 
  that 
  this 
  feeling 
  of 
  bodily 
  effort 
  

   is 
  more 
  immediately 
  associated 
  with 
  the 
  conception 
  of 
  force 
  than 
  of 
  

   mass, 
  so 
  that 
  it 
  may 
  be 
  necessary 
  to 
  regard 
  mass 
  as 
  being 
  derived 
  

   from 
  it 
  by 
  combination 
  with 
  the 
  concept 
  of 
  acceleration, 
  which 
  is 
  a 
  

   special 
  relationship 
  between 
  spatial 
  and 
  temporal 
  magnitudes. 
  It 
  

   is 
  of 
  interest 
  that 
  the 
  kinaesthetic 
  quality, 
  which 
  is 
  one 
  of 
  the 
  cardinal 
  

   constituents 
  of 
  internal 
  experience, 
  should 
  turn 
  out 
  to 
  be 
  about 
  the 
  

   last 
  directly 
  qualitative 
  experimental 
  factor 
  to 
  remain 
  in 
  the 
  system 
  

   of 
  physical 
  thinking. 
  

  

  Space, 
  from 
  the 
  psychological 
  point 
  of 
  view, 
  may 
  in 
  some 
  cases 
  

   be 
  regarded 
  as 
  forming 
  a 
  distinctive 
  qualitative 
  constituent 
  of 
  con- 
  

   sciousness. 
  There 
  are 
  sensations 
  for 
  example 
  which 
  possess 
  a 
  spatial 
  

   or 
  extensive 
  quality 
  while 
  others 
  are 
  lacking 
  in 
  this 
  attribute. 
  In 
  

   the 
  majority 
  of 
  instances 
  however' 
  we 
  are 
  forced 
  to 
  regard 
  space 
  in 
  

   experience 
  as 
  representing 
  a 
  form 
  of 
  combination 
  of 
  elementary 
  qualities 
  

   rather 
  than 
  as 
  comprising 
  such 
  a 
  quality 
  in 
  itself. 
  In 
  this 
  sense 
  space 
  

   is 
  a 
  category 
  of 
  structure 
  rather 
  than 
  of 
  substance. 
  Visually 
  perceived 
  

  

  