PREFACE 
POLITICAL Economy Is, and has been for some years, in a 
transitional state, which is proof of its vitality. On the 
one side it is becoming more abstract, and on the other side 
it is becoming more realistic. The two movements are 
not in the least opposed, unless in the sense that they act 
and react on each other incessantly to the great advance 
ment of the study. Much modern Economic science 
is being increasingly assimilated in form and method to 
the Natural sciences. In chemical and physical labora 
tories which can pretend to any distinction realistic 
researching never stops ; but speculation as regards the 
fundamentals of chemistry and physics continue and 
must continue. In the great laboratory of the world a 
multitude of realistic researches remain to be made by 
economists, and it is only as they are made that the 
science of economics will develop satisfactorily ; but to 
attack the ultra-abstract and mathematical economists 
on that account, in the supposed interests of realism, 
is suicidal. Of this book speculative results of a very 
general kind are the substance. 
I have to thank Mr. A. Fingland Jack, Lecturer on 
Economics and Commerce in the University of Manchester 
for his kind assistance with the proofs, 
The University, 
Manchester, June, 1912