Children can learn to count without understanding the meaning of numbers. Familiarity with a concept is not always sufficient for knowing the words used to express it. Songs are useful in helping children remember the order in which familiar words occur. There are some things that children cannot learn without the aid of songs.
Several three-year-olds who had learned to count to ten were trying to learn their telephone numbers. Although each child was familiar with the names of all the digits, no child could remember his or her phone number. Their teacher then taught each child a song whose lyrics contained his or her phone number. By the end of the day the children could remember their telephone numbers.
The situation described above best illustrates which one of the following propositions?