CHAPTER II 



THE FACTS OF SCIENCE 



S I . — T]ie Reality of Things 



In our first chapter we have frequently spoken of the 

 classification of facts as the basis of the scientific method ; 

 we have also had occasion to use the words real and 

 unreal, universe and phcnojuenon. It is proper, therefore, 

 that before proceeding further we should endeavour to 

 clear up our ideas as to what these terms signify. We 

 must strive to define a little more closely in what the 

 material of science consists. We have seen that the 

 legitimate field of science embraces all the mental and 

 physical facts of the universe. But what are these facts in 

 themselves, and what is for us the criterion of their reality? 

 Let us start our investigation with some " external 

 object," and as apparent simplicity will be satisfied by 

 taking a familiar requisite of the author's calling, namely, 

 a blackboard, let us take it.^ We find an outer rect- 

 angular frame of brownish-yellow colour, which on closer 

 inspection we presume to be wood, surrounding an 

 inner fairly smooth surface painted black. We can 

 measure a certain height, thickness, and breadth, we notice 

 a certain degree of hardness, weight, resistance to breaking, 

 and, if we examine further, a certain temperature, for the 

 board feels to us cold or warm. Now although the black- 

 board at first sight appears a very simple object, we see 



1 The blackboard as an "object-lesson" is such a favourite instance with 

 the writer, that the reader will perhaps pardon him the use of it here. Seine 

 Mundart klebt jedem an. 



