io LIFE AND HABIT. 



act of exercise. We notice any obstacle in our path, 

 but it is plain we do not notice that we perceive 

 much that we have nevertheless been perceiving ; for 

 if a man goes down a lane by night he will stumble over 

 many things which he would have avoided by day, al- 

 though he would not have noticed them. Yet time was 

 when walking was to each one of us a new and arduous 

 task — as arduous as we should now find it to wheel a 

 wheelbarrow on a tight-rope ; whereas, at present, 

 though we can think of our steps to a certain extent 

 without checking our power to walk, we certainly can- 

 not consider our muscular action in detail without 

 having to come to a dead stop. 



Talking — especially in one's mother tongue — may 

 serve as a last example. We find it impossible to 

 follow the muscular action of the mouth and tongue 

 in framing every letter or syllable we utter. We have 

 probably spoken for years and years before we became 

 aware that the letter b is a labial sound, and until we 

 have to utter a word which is difficult from its un- 

 familiarity we speak " trippingly on the tongue " with 

 no attention except to the substance of what we 

 wish to say. Yet talking was not always the easy 

 matter to us which it is at present — as we perceive 

 more readily when we are learning a new language 

 which it may take us months to master. Nevertheless, 

 when we have once mastered it we speak it without 

 further consciousness of knowledge or memory, as 

 regards the more common words, and without even 

 noticing our unconsciousness. Here, as in the other 

 instances already given, as long as we did not know 



