ABSTRACT
The rather controversial implication I made at the end of the last chapter that not all the errors a child makes in his language behaviour are indicative of lack of skill needs some explanation. Take the words ‘bringed’ and ‘mouses’. These are errors, in the sense that the correct forms are ‘brought’ and ‘mice’. But the fact that they are virtuous errors becomes clear when we consider how the child could have said such words. He almost certainly did not remember them from someone else’s utterance and imitate them; for most of the mouses he has met will have been called mice. He must have formed the word for himself by adding ‘s’ to the word ‘mouse’. In other words, he has acquired the regular rule that to form a plural you add ‘s’ or ‘es’. What he has failed to do is to acquire the irregularities to this rule. So one may conclude that at least up to the age of four, five, or six, the word ‘mouses’ represents a virtuous error, in that it indicates that the child has grasped the basic way of combining plural morphemes with other morphemes.
