488 Edward Livingston Youmans. 



was understood, even in periods of earliest barbarism, that 

 with scarcity the price of food rises ; and that bits of metal 

 may be made serviceable to carry on exchanges : these 

 were the germs which have grown into a body of definite 

 and connected truths, which form the science of political 

 economy. Again, at the earliest dawn of intelligence, men 

 knew that objects seen together are apt to be remembered 

 together : this rudimental fact has been expanded in 

 modern times into the science of psychology. 



Such being the essential character of science, the ques- 

 tion next arises, How much does the term comprehend ? 

 Our knowledge of Nature is all of this growing or pro- 

 gressive kind. In every aspect of the natural world the 

 explanations were at first crude and imperfect, and have 

 gradually ripened into greater distinctness and precision. 

 We are thus brought to the full breadth of meaning of the 

 term science, which is nothing less than the latest and 

 truest interpretation of the order of the world at which the 

 human mind has arrived. It is the perfected mode of 

 thinking in its application to all the phenomena of Nature 

 which can become the subjects of thought. 



But it will be asked, What do you mean by Nature ? 

 We mean the whole system of appearances objects and 

 actions by which we are surrounded in the present state 

 of being. It includes the entire realm of existence and 

 activity, material and mental, with all their interconnec- 

 tions and interactions, which constitute the environment of 

 man. As the material world is but part of the natural or- 

 der, physical knowledge is but a part of science. Our 

 knowledge of mind and character, of the springs and limits 

 of human action, of the relations of men and the conditions 

 of social welfare, may be either loose and confused, or 

 definite and accurate. This kind of knowledge conforms 

 equally to the conditions of growth, and therefore has its 

 true scientific aspects. But we can only comprehend the 



