FIRST PRINCIPLES 33 



from a single presentation of sense. Whether or not the 

 mind perceives them, however, all sensations produce their 

 effects upon the organism. Sensations which the mind per- 

 ceives are the raw materials which it works into a product by 

 which intelligence is made manifest. Mental action is a 

 weaving of sensations into a pattern, and the expression 

 of this pattern in act or thought. 



If we try to figure to ourselves the mental activities of any 

 animal, we recognise at once that its thoughts must take the 

 colour of the sense by which they are chiefly prompted. A 

 dog, for example, does not recognise "a family likeness," 

 but a family smell. In a day of happy wandering down the 

 village street and through the lanes it pays no attention to 

 the picturesque. As it lies in front of the fire, reviewing the 

 experiences of the day, it recalls a long succession of sugges- 

 tive smells. It is the cheek-bristles of the otter which 

 vibrate with excitement as it remembers the slippery-sided 

 salmon it nearly mistook for an alder-root. The cat twitches 

 its ears as it dreams of bursting unannounced into a 

 seminary of mice. If we wish in any degree to realise what 

 our thoughts would be like if we were to exchange our brain 

 for the brain of some other animal, we must ask first : 

 Which of the five sense-organs is the one through which 

 this particular animal chiefly looks out upon the world? 



Before we set out to explore the world it is well that we 

 should inquire into the credentials of the agents upon whom 

 we shall depend for information. These agents are 



1. The Nose. A poor thing to depend upon, and turned 

 to base uses. We rely upon it chiefly to tell us when we are 

 near drains or other receptacles for matter which experience 

 has shown us to be noxious. We speak of such smells as 

 "nasty. " " Nice smells " are not for the most part nice in 

 themselves, but scents which, like musk, frangipanni, aro- 

 matic oils, etc. , are peculiarly efficient in antagonising nasty 

 smells ; for the sense of smell in Man is almost useless for 

 analysis ; it can hardly distinguish one scent in the presence 



