322 THE MONTESSORI METHOD
ments through channels already rendered permeable by the corresponding muscular sensations.
DEFECTS OF LANGUAGE DUE TO LACK OF EDUCATION
Defects and imperfections of language are in part due to organic causes, consisting in malformations or in pathological alterations of the nervous system; but in part they are connected with functional defects acquired in the period of the formation of language and consist in an erratic pronunciation of the component sounds of the spoken word. Such errors are acquired by the child who hears words imperfectly pronounced, or hears bad speech. The dialectic accent enters into this category; but there also enter vicious habits which make the natural defects of the articulate language of childhood persist in the child, or which provoke in him by imitation the defects of language peculiar to the persons who surrounded him in his childhood.
The normal defects of child language are due to the fact that the complicated muscular agencies of the organs of articulate language do not yet function well and are consequently incapable of reproducing the sound which was the sensory stimulus of a certain innate movement. The association of the movements necessary to the articulation of the spoken words is established little by little. The result is a language made of words with sounds which are imperfect and often lacking (whence incomplete words). Such defects are grouped under the name blcesitas and are especially due to the fact that the child is not yet capable of directing the movements of his tongue. They comprise chiefly: sigmatism or imperfect pronunciation of s; rhotacism or imperfect pronunciation of r; lambdacism or imperfect pronunciation of I; gam-