Final answer:
Auggie's technique of using objects to represent larger ideas in his writing is known as symbolism, a literary device that imbues objects with a deeper meaning.
Step-by-step explanation:
The technique used by Auggie in his writing where simple ideas or objects represent something else is best described by the term symbolism. Symbolism is a literary device where symbols are used to represent larger concepts or ideas beyond their literal sense. A common example of symbolism in literature is when a flag is used to represent concepts such as freedom, sacrifice, or oppression. This technique differs from metaphors, which make direct comparisons, similes, which use 'like' or 'as' in comparisons, and personification, which gives human traits to non-human entities.