﻿LENGTHENING 
  OF 
  HUMAN 
  LIFE 
  — 
  FISHEE 
  

  

  549 
  

  

  the 
  vertical, 
  approaching 
  an 
  impassable 
  barrier 
  or 
  " 
  asymptote." 
  On 
  

   the 
  basis, 
  therefore, 
  of 
  the 
  only 
  statistical 
  evidence 
  we 
  possess 
  we 
  find 
  

   absolutely 
  no 
  hint 
  of 
  any 
  definite 
  limit 
  to 
  human 
  life. 
  On 
  the 
  con- 
  

   trary, 
  the 
  right-hand 
  end 
  of 
  the 
  curve 
  hints 
  the 
  exact 
  opposite. 
  

  

  It 
  is 
  dangerous 
  to 
  extrapolate 
  any 
  statistical 
  curve, 
  for 
  there 
  is 
  no 
  

   telling 
  which 
  way 
  it 
  will 
  turn; 
  but 
  if 
  we 
  assume 
  that 
  the 
  mortality 
  

   of 
  centenarians 
  is 
  not 
  over 
  50 
  per 
  cent 
  per 
  annum, 
  which 
  is 
  conserva- 
  

   tive 
  so 
  far 
  as 
  our 
  scanty 
  facts 
  go, 
  we 
  would 
  have 
  at 
  least 
  one 
  cen- 
  

   tenarian 
  out 
  of 
  a 
  thousand 
  reaching 
  110 
  years, 
  and 
  of 
  those 
  who 
  reach 
  

   110, 
  one 
  out 
  of 
  a 
  thousand 
  reaching 
  120, 
  and 
  so 
  on 
  indefinitely. 
  There 
  

  

  CHART 
  IV 
  

   EXPECTATION 
  OF 
  LIFE 
  

  

  (At 
  BreTH) 
  

   Chances 
  in 
  Past 
  400 
  Yeaks 
  

  

  Geneva 
  

  

  Massachusetts 
  

  

  U. 
  S. 
  Registration 
  States 
  

  

  16th 
  17th 
  18th 
  

   Coittiry 
  Century 
  Coitnry 
  

  

  1789 
  1890 
  1897 
  1900 
  

  

  1910 
  

  

  1920 
  1921 
  

  

  21 
  Yrs. 
  26Yrs. 
  34 
  Yrs. 
  55 
  Yrs. 
  4j 
  Yrs. 
  45 
  Yrs. 
  49 
  Yrs. 
  -51 
  Vrs. 
  55 
  Yrs. 
  58 
  Yrs. 
  

   Fig. 
  4 
  — 
  Most 
  of 
  the 
  gain 
  due 
  to 
  improvement 
  in 
  death 
  rates 
  under 
  age 
  45 
  

  

  would 
  be 
  one 
  to 
  reach 
  140 
  out 
  of 
  a 
  trillion 
  centenarians 
  and 
  one 
  

   person 
  would 
  reach 
  180 
  out 
  a 
  trillion 
  trillion 
  centenarians. 
  Such 
  a 
  

   " 
  law 
  " 
  of 
  mortality 
  does 
  not 
  seem 
  unreasonable. 
  Whether 
  the 
  

   chance 
  of 
  reaching 
  180 
  under 
  this 
  law 
  is 
  greater 
  or 
  less 
  than 
  the 
  

   proverbial 
  chance 
  that 
  a 
  blindfolded 
  man 
  could 
  write 
  Hamlet 
  by 
  set- 
  

   ting 
  type 
  picked 
  out 
  by 
  random, 
  I 
  do 
  not 
  know. 
  I 
  am 
  not 
  stressing 
  

   the 
  practical 
  importance 
  of 
  such 
  slim 
  chances. 
  

  

  What 
  I 
  am 
  stressing 
  is 
  that 
  we 
  must 
  apparently 
  give 
  up 
  the 
  con- 
  

   cept 
  of 
  any 
  definite 
  life 
  span 
  and 
  substitute 
  the 
  concept 
  merely 
  of 
  

   74906—28 
  36 
  

  

  