VllJ 



INDUCTION. 



1S7 



tions deductively from four laws of correction, but my 

 correspondents found that three simpler laws, equivalent 

 to the four more complex ones, were the best answer ; these 

 laws are as follows : a = ac, b = cd, d = E/i 



In case other readers should like to test their skill in the 

 inductive or inverse problem, I give below several series 

 of combinations forming problems of graduated difficulty. 



A B c 



A b c 



a B C 



.OBLEil 



ABC 



A 6 

 a B C 

 a B c 



ABC 

 A b C 

 a B C 

 a B c 

 ale 



ABCD 

 A be D 

 a B c d 

 a b C d- 



ABCD 

 A BCd 



A 1C D 

 A I e D 

 a R (! D 

 re B c 1) 

 a B c d 

 a b C d 



PROBLEM vi 



A B C D E 



A B C d e 

 A B c D E 

 A B c d e 

 AbCD E 

 a 13 C D E 

 a B C d e 

 ab C D E 

 abode 



A ft c D e 

 oBC d R 

 a b C d E 



in. 



ABCDE 

 ABC De 

 A B C d e 

 A B c d e 

 AbC DE 

 A b c d E 

 A 6 c d e 

 a B C D e 

 a B C d e 

 a B c D e 



a b C D e 



a b C .i E 



a b c I) e 



n 6 c d E 



PROBLEM n. 



A B c D E F 



A B c D e F 



A b C D e/ 



A b c D E / 



A /> c D e / 



A b c d E F 



A b c d e F 



Be BE F 



Be D e F 



Be d E F 



b C D E F 



b C 1) e F 



6 C D e / 



b c D e f 



b c I) E / 



PROBLEM x. 



ABC DeF 



ABc D E/ 



A b C D E F 



A bC De F 



b c D F 



BC DE j 



B c D B/ 



bC D e F 



b C de F 



b c D e / 



b c d e J 



Induction of Simple Identities. 



Many important laws of nature are expressible in the 

 form of simple identities, and I can at once adduce them 

 as examples to illustrate what I have said of the difficulty 

 of the inverse process of induction. Two phenomena are 

 conjoined. Thus all gravitating matter is exactly co- 

 incident with all matter possessing inertia ; where one 



