What does the dual perspective show in Twain's autobiography from boyhood to adulthood?

The dual perspective in Twain's autobiography allows readers to see events and experiences through both the eyes of the young boy and the reflective adult. This provides a richer understanding of the narrator's growth, development, and changing perceptions as he transitions from boyhood to adulthood. It also adds depth and complexity to the narrative by showing how the same events can be interpreted differently by the younger and older versions of the author.