CHAPTER I. 



WHY TO STUDY 



Two hundred and sixteen (216) separate and distinct combinations 

 can be formed by three dice of different design, as shown by the 

 drawing (Fig. 1). 



On the principal of chance, if these three dice are thrown an infinite 

 number of times, each one of the 216 combinations will appear just as 

 often as every other one. 



This is true only if the dice are not weighted. Combinations being 

 formed by three dice have been chosen because there are usually at least 

 three alternatives in any case Avhere a man's judgment or opinion is 

 required or asked for. Further, an analogy can be found in the com- 

 plete human individual where the 



Physical 



Mental and 



Moral 



must ever We considered; while on the strictly scientific basis, everything 

 that a man is, or* can be, depends upon the three factors: 



Inheritance 



Environment and 



Training. 



Or, again, no opinion worth anything can be formed without the fol- 

 lowing three factors being taken into consideration : 



Obtaining the facts 



Reasoning thereon 



Forming a judgment or conclusion. 



Each dice possessing six sides may be compared to the many facts, 

 conditions, or possibilities that go to make up any one of the three great 

 factors appearing in the tables above. 



It is self-evident from this that in any given case where there are 

 three factors with six possibilities contingent upon each, unless life's 

 dice are weighted by knowledge, a man's opinion stands only one chance 

 in 216 of being correct. 



The almost ideal laboratory evidence that substantiates these 

 statements is found in the fact that out of three thousand cases 

 at one of our leading hospitals, it has been found the diagnosticians 

 were correct only 53.5% of the time.* If, at our most important insti- 

 tutions, the ablest and best trained men, working with the finest equip- 

 ment obtainable, are correct only approximately one-half the time, it 

 means that on the principle of chance, when anyone passes an opinion 



*"Diagnostic Pitfalls Identified During a Study of Three Thousand Autopsies," by Richard C. 

 Cabot, M.D. Journal of the American Medical Association, pp. 2295-2298, Dec. 28, 1912. 



