﻿LECTUKE 
  IV. 
  

   ORGANISM 
  AND 
  MECHANISM. 
  

  

  1. 
  Is 
  Organism 
  More 
  than 
  Mechanism? 
  2. 
  Chemical 
  and 
  

   Physical 
  Laws 
  apply 
  to 
  Organisms. 
  3. 
  Some 
  Difficulties 
  in 
  

   the 
  Application 
  of 
  Physical 
  and 
  Chemical 
  Formula 
  to 
  Organ- 
  

   isms. 
  4. 
  Criticism 
  of 
  Mechanistic 
  Descriptions 
  of 
  Everyday 
  

   Functions. 
  5. 
  Criticism 
  of 
  Mechanistic 
  Descriptions 
  of 
  

   Animal 
  Behaviour. 
  6. 
  Difficulty 
  of 
  Applying 
  Mechanistic 
  

   Formula 
  to 
  Development. 
  7. 
  Difficulty 
  of 
  Applying 
  Mecha- 
  

   nistic 
  Formula 
  to 
  Organic 
  Evolution. 
  8. 
  Answers 
  to 
  Criti- 
  

   cisms. 
  

  

  1. 
  Is 
  Organism 
  More 
  than 
  Mechanism? 
  

  

  ACCORDING 
  to 
  Kirchhoffs 
  famous 
  definition 
  (1876), 
  the 
  

   task 
  of 
  mechanics 
  is 
  " 
  to 
  describe 
  completely 
  and 
  in 
  the 
  sim- 
  

   plest 
  manner 
  the 
  motions 
  which 
  take 
  place 
  in 
  nature 
  ". 
  

   When 
  we 
  give 
  a 
  mechanical 
  description 
  of 
  an 
  occurrence 
  

   the 
  eruption 
  of 
  Vesuvius, 
  the 
  bursting 
  of 
  the 
  broom-pods, 
  

   or 
  the 
  curling 
  of 
  the 
  non-living 
  tendrils 
  of 
  a 
  mermaid's 
  purse 
  

   it 
  is 
  in 
  terms 
  of 
  matter 
  and 
  motion, 
  or 
  in 
  chemico-physical 
  

   terms 
  which 
  are 
  believed 
  to 
  be 
  reducible 
  to 
  those 
  of 
  matter 
  

   and 
  motion. 
  The 
  mechanical 
  account 
  is 
  as 
  such 
  entirely 
  

   satisfactory 
  when 
  it 
  enables 
  us 
  to 
  see 
  a 
  process 
  as 
  a 
  con- 
  

   tinuous 
  series 
  of 
  necessarily 
  concatenated 
  mechanical 
  opera- 
  

   tions 
  like 
  those 
  which 
  occur 
  in 
  the 
  slow 
  movement 
  of 
  a 
  

   glacier, 
  or 
  like 
  the 
  successive 
  explosions 
  which 
  mark 
  the 
  

   extension 
  of 
  a 
  rapidly 
  spreading 
  conflagration. 
  We 
  shall 
  

   use 
  the 
  slightly 
  wider 
  term 
  mechanistic 
  to 
  include 
  either 
  a 
  

   matter-and-motion 
  description, 
  which 
  is 
  in 
  the 
  strict 
  sense 
  

   mechanical, 
  or 
  a 
  more 
  dynamical 
  description 
  in 
  which 
  the 
  

  

  107 
  

  

  