The answer is “themes”. Both the tiger and the lamb convey similar messages, also called themes. By definition, a theme is a main idea, an underlying message or meaning of a literary work that can be made direct or indirectly. The theme in both poems by William Blake (“The Lamb” and “The Tyger”) is creation and origin. For instance, in the poem “The Tyger”, the narrator questions how the same God could create such a gentle creature as the lamb and also a terrifying creature as the tiger (“Did he who made the Lamb make thee?”).