14 PROGRESS OF SCIENCE IN THE CENTURY. 



ties of the student who always has his microscope 

 wrongly focussed and is satisfied with the ill-defined 

 image, or of the other whose dissection is invariably 

 either a mince or a tangle, or of the other who is 

 never quite sure whether he knows a thing or not. 

 Ignorance in itself is no particular reproach; the 

 point is to know when we know and when we don't, 

 and it is one of the characteristics of the scientific 

 mood that it will have yes or no to this question. 



Those of the scientific mood are mainly trying to 

 construct a working-thought-model of the outer 

 world, to form a mental image which will be a living 

 picture, an intellectual cinematograph. In other 

 words they would make the world translucent, as 

 translucent as the human body becomes to the skilled 

 anatomist. 



Clerk-Maxwell's boyish question " What is the 

 go of this ? " and, when put off with some verbal- 

 ism, " What is the particular go of this ? " is a ques- 

 tion characteristic of the scientific mood, which may 

 be applied to any order of facts. 



The mole has a sort of half-finished lens, which 

 is physically incapable of throwing a precise image 

 on the retina. If there is any image, it must be 

 a blurred tangle of lines. In our busy lives, we tend 

 to acquire mole-like lenses in regard to particular 

 orders of facts ; we see certain things clearly, others 

 are blurs; but the scientific mood is in continual 

 protest against obscurities, insisting upon lucidity. 



Thus we feel the force of one of Bacon's most 

 historically true aphorisms, which declares " Truth 

 to emerge sooner from error than from confusion." 

 It is a great step when a false notion is formulated. 

 The definitising of error has been the beginning of 

 its disappearance. As soon as the evil genie of the 



