NATURE OF INTERPRETATION, 45 
of hereditary) and the accurate knowledge of what actually 
takes place ........ is the same as the difference between 
common sense and science, and the same as the difference 
between that which stands to reason and that which rests 
on evidence.” 
The progressive attitude in natural science is that of 
scepticism, and most particularly should we guard against the 
misuse of the preconceived idea. As a stimulus to further 
work it is useful; as a line of tentative investigation it is 
invaluable ; but as a guiding principle in inquiry it is to be 
heartily condemned. 
Generally, I think, we are more interested in proving our 
theory right than in proving it wrong. Or, to state this 
differently, our real object in studying natural phenomena 
is often enough the pleasure of seeing how beautifully they fit 
in to our interpretation of them, rather than the knowledge 
of how our interpretation fits the facts. 
Having made as good a theory as we can, we should 
endeavour to disprove it, for then, indeed, are we aiming at 
truth and not at romance. 
B—THE NATURE OF INTERPRETATION. 
In the first part of my Paper I attempted to how that our 
methods of studying Nature are sometimes open to the objec- 
tion that, inasmuch as we may confuse description with 
interpretation, we are liable to draw very wrong conclusions ; 
that this is the result of the very human desire to prove our 
point of view. Ideally, theory should not be trusted till all 
the facts bearing upon it have been collected, and all the 
exceptions to the apparent rule appreciated. We should 
always be careful to see that we are not led into any looseness 
of statement or ambiguity where technical terms are concerned. 
We should always approach the problems of Nature with a 
perfectly open mind, being ready at any moment to throw 
over our most treasured theory in favour of another, or to 
adapt it as may be necessary when occasion requires. 
In this part of my Paper we shall endeavour to understand 
what we are actually doing when we interpret Nature, and 
