8 
POLITICAL ECONOMY 
particularly by Dr. Marshall. Though the 
new generalisations were suggested at many 
points by mathematics, it is perfectly easy to 
represent them in simple language which 
implies no mathematical knowledge ; and 
I shall try so to do. Indeed the fundamental 
ideas in modern economic theory are by no 
means difficult to understand ; and if there 
fore I should fail in my object it will be my 
fault and not the fault of the subject. Far 
from confusing simple issues the new work 
has clarified what was previously obscure 
and rendered economic theory easier for 
everybody to grasp ; but at the same time it 
must be admitted that it puts a greater 
strain on the reader’s powers of concentration, 
inasmuch as it rejects all vague conceptions 
and loose reasoning and insists on exactness. 
Whatever be the method of treatment 
adopted, the scope or nature of economic 
studies calls first for discussion. The substance 
of economics consists in all economic facts. 
Economic facts may be described as any facts 
which have relation at the same time to man 
on the one hand and wealth on the other ; 
and for our present purpose it is sufficient to 
think of wealth as made up of all the things 
desired by man which can be attained only 
with the expenditure of human effort. Now