Early echoic behavior in young children is often very wide of the mark; the parent must reinforce very imperfect matches to keep the behavior in strength at all. We might say that the child “has no way of knowing how to execute a particular response for the first time”; strictly speaking, we should say that the response is not yet a function of any variable available to the parent. Nothing in the pattern to be echoed will help until some overlapping echoic behavior occurs. “Trying to make the right sound,” like trying to find one’s hat, consists of emitting as many different responses as possible until the right one appears. (pp. 59-60)
