20 OPERATIONS OF REASON 



or a teacher. Another remarkable difference subsists 

 between reason and instinct : the fomier is directed 

 by motives, whilst the latter seems to have no other 

 design than the gratification of an irresistible impulse. 

 Men weigh consequences, and act according to their 

 view of the readiest means of producing certain effects : 

 animals perform their instinctive habits without fore- 

 seeing the result. 



•^^'As an example of this distinction, let us trace 

 the operations of a man going to erect a mill. First 

 he calculates the extent of his means, and whether 

 his finances are adequate to the undertaking. He 

 chooses a proper situation ; purchases timber ; engages 

 numbers of his fellow-men, skilled in different arts, to 

 assist him — bricklayers, carpenters, and blacksmiths. 

 For each he provides proper tools and materials ; and 

 when they are set to work, every part is contrived to 

 answer a particular purpose, and is adapted to a de- 

 termined place. He also takes into consideration the 

 use for which it is designed ; whether it is to grind 

 corn, or any other article that may require different 

 machinery : and lastly, whether it is to be set in 

 motion by wind, water, or steam. All this demands 

 reflection, contrivance, design, science, and experience ; 

 of which the most sagacious animal that was ever dis- 

 covered is wholly incapable. A bird lays the twigs 

 for her nest, and lines it in the same manner as her 



