But politics are studied, as Aristotle said, 'for the sake of action rather than of knowledge,'[49] and the student is bound, sooner or later, to ask himself what will be the effect of a change in his science upon that political world in which he lives and works. [49] _Ethics_, Bk. I. ch. iii. (6). [Greek: epeidê tò telos [tês politikês] estìn ou gnêsis allà praxis.] One can imagine, for instance, that a professor of politics in Columbia University, who had just taken part as a 'Mugwump' in a well-fought but entirely unsuccessful campaign against Tammany Hall, might say: 'The finer and more accurate the processes of political science become, the less do they count in politics. Astronomers invent every year more delicate methods of forecasting the movements of the stars, but cannot with all their skill divert one star an inch from its course. So we students of politics will find that our growing knowledge brings us only a growing sense of helplessness. We may learn from our science to estimate exactly the forces exerted by the syndicated newspaper press, by the liquor saloons, or by the blind instincts of class and nationality and race; but how can we learn to control them? The fact that we think about these things in a new way will not win elections or prevent wars.' I propose, therefore, in this second part of my book to discuss how far the new tendencies which are beginning to transform the science of politics are likely also to make themselves felt as a new political force. I shall try to estimate the probable influence of these tendencies, not only on the student or the trained politician, but on the ordinary citizen whom political science reaches only at second or third hand; and, with that intention, shall treat in successive chapters their relation to our ideals of political morality, to the form and working of the representative and official machinery of the State, and to the possibilities of international and inter-racial understanding. This chapter deals from that point of view with their probable influence on political morality. In using that term I do not mean to imply that certain acts are moral when done from political motives which would not be moral if done from other motives, or _vice versâ_, but to emphasise the fact that there are certain ethical questions which can only be studied in close connection with political science. There are, of course, points of conduct which are common to all occupations. We must all try to be kind, and honest, and industrious, and we expect the general teachers of morals to help us to do so. But every occupation has also its special problems, which must be stated by its own students before they can be dealt with by the moralist at all. In politics the most important of these special questions of conduct is concerned with the relation between the process by which the politician forms his own opinions and purposes, and that by which he influences the opinions and purposes of others.