PHILOSOPHICAL SOCIETY OF WASHINGTON. 41 



research. There is no such division recognized as that of useful 

 and useless kuowledge. The ultimate aim is nothing less than that 

 of bringing all the phenomena of nature under laws as exact as 

 those which govern the planetary motions. 



Now the pursuit of any high object in this spirit commands from 

 men of wide views that respect which is felt towards all exertion 

 having in view more elevated objects than the pursuit of gain. 

 Accordingly it is very natural to classify scientists, and philos- 

 ophers with the men who in all ages have sought after learning 

 instead of utility. But there is another aspect of the question 

 which will show the relations of scientific advance to the practical 

 affairs of life in a different light. I make bold to say that the 

 greatest want of the day, from a purely practical point of view, is 

 the more general introduction of the scientific method and the 

 scientific spirit into the discussion of those political and social pro- 

 blems which we encounter on our road to a higher plane of public 

 well being. Far from using methods too refined for practical pur- 

 poses, what most distinguishes scientific from other thought is the 

 introduction of the methods of practical life into the discussion of 

 abstract general problems. A single instance will illustrate the 

 lesson I wish to enforce. 



The question of the tariff is, from a practical point of view, one 

 of the most important with which our legislators will have to deal 

 during the next few years. The widest diversity of opinion exists 

 as to the best policy to be pursued in collecting a revenue from 

 imports. Opposing interests contend against each other without 

 any common basis of fact or principle on which a conclusion can 

 be reached. The opinions of intelligent men differ almost as widely 

 as those of the men who are immediately interested. But all will 

 admit that public action in this direction should be dictated by 

 one guiding principle — that the greatest good of the community is 

 to be sought after. That policy is the best which will most pro- 

 mote this good. Nor is there any serious difference of opinion as 

 to the nature of the good to be had in view ; it is in a word the 

 increase of the national wealth and prosperity. The question on 

 which opinions fundamentally differ is that of the effects of a higher 

 or lower rate of duty upon the interests of the public. If it were 

 possible to foresee, with an approach to certainty, what effect a given 

 tariff would have upon the producers and consumers of an article 

 taxed, and, indirectly, upon each member of the community in any 



