COMMON THINGS MAN. 



and increase of strength in the muscles which move them, and 

 about the close of the first year this strength bears such a 

 relation to the weight of the body, that the child is enabled to 

 support itself on its legs, and by gradual practice acquires the 

 ability to walk. 



36. It is generally assumed that man is distinguished from the 

 inferior animals by the substitution of reason for instinct, and in 

 this way it is explained how the young of other animals manifest 

 at the moment of birth the possession of powers and faculties, 

 which, in the case of the young of the human race, are acquired 

 only by long practice and slow degrees. It is therefore con- 

 tended, that while the young of the lower animals are governed 

 exclusively by instinct, the young of man is as exclusively 

 governed by reason, the conclusions of which are based upon 

 experience. The acts prompted by instinct are performed as 

 perfectly at first as at last, and undergo no progressive improve- 

 ment ; while, on the contrary, the dictates of reason being based 

 upon experience, cannot be issued by the mind until the results of 

 that experience, which are their only data, have been developed. 

 It has, therefore, been argued, that the helplessness of the infant, 

 and the slow and gradual progress of the exercise of its senses 

 and members, must be explained by the total absence of instinct. 

 This conclusion, however, it seems cannot be admitted in its 

 absolute sense, and observation and experience show that it 

 requires considerable qualification. Many eminent physiologists 

 impugn it, and Sir Charles Bell has even expressed a doubt 

 whether the actions of the body, if not first instinctive or 

 prompted by innate sensibilities, would ever be exercised under 

 the exclusive influence of reason. The sensibilities and motions of 

 the lips and tongue are, according to him, perfect at birth ; and 

 the fear of falling is manifested by the infant long before the 

 results of experience can suggest it. The hand, destined to 

 become the instrument not only for the improvement of the senses, 

 but for the development of the mental faculties, is absolutely 

 powerless in the infant. Although capable of expressing pain, it 

 is unconscious of the part injured. But the lips and tongue 

 immediately betray their sensibility. Later, the infant puts its 

 fingers into its mouth to suck them, and so soon as they are 

 capable of grasping, whatever they lay hold of is carried to the 

 mouth. 



" The first office of the hand, then, is to exercise the sensibility 

 of the mouth, and the infant as certainly questions the reality of 

 things by that test, as does the dog by its acute sense of smelling. 

 In the infant the sense of the lips and tongue is resigned in favour 

 of that of vision, only when the exercise of the eye has improved 

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