This study examined the hypothesis of a linear, bipolar continuum, with the principles of oral language at one end and those of written language at the other. Six sources of language were identified and arranged along the continuum, to reflect their underlying governing principles: spontaneous oral language of children, children's folk songs, songs for children, folk stories, recent stories for children, and basal readers. Comparisons of specified structural characteristics across all language categories revealed a multidirectional relationship, rather than a linear, bipolar relationship, among all six categories. The language of children showed little structural similarity to other categories; children's folk songs and songs for children showed greater structural similarity to each other than to any other category; and written folk stories, stories for children, and basal readers showed structural similarities. The similarities and differences between the structurally analyzed language selections were interpreted as indicating a variety of "sets" of underlying principles governing a variety of forms of language expression. (Author/AA)