METHOD OF DISCOVERY. 61 



the relations of certain phenomena, we prove that some 

 stand in the position of causes towards the others. 



I want to put the case clearly before you, and [ will 

 therefore show you what I mean by another familiar 

 example. I will suppose that one of you, on coming 

 down in the morning to the parlour of your house, finds 

 that a tea-pot and some spoons which had been left in 

 the room on the previous evening are gone, — the win- 

 dow is open, and you observe the mark of a dirty hand 

 on the window-frame, and perhaps, in addition to that, 

 you notice the impress of a hob-nailed shoe on the 

 gravel outside. All these phenomena have struck your 

 attention instantly, and before; two minutes have passed 

 you say, "Oh, somebody has broken open the window, 

 entered the room, and run off with the spoons and the 

 tea-pot! " That speech is out of your mouth in a mo- 

 ment. And you will probably add, "I know there 

 has ; T am quite sure of it ! " You mean to say exactly 

 what you know ; but in reality what you have said has 

 been the expression of what is, in all essential particu- 

 lars, a Hypothesis. You do not know it at all ; it is 

 nothing but a hypothesis rapidly framed in your own 

 mind ! And it is a hypothesis founded on a long train 

 of inductions and deductions. 



What are those inductions and deductions, and how 

 have you got at this hypothesis? You have observed, 

 in the first place, that the window is open ; but by a 

 train of reasoning involving many Inductions and De- 

 ductions, you have probably arrived long before at the 

 General Law — and a very good one it is — that windows 

 do not open of themselves ; and you therefore conclude 

 that something has opened the window. A second 

 general law that you have arrived at in the same way 



