Piled like bricks in stacks a dozen high
A telling simile. ‘Like bricks’ suggests a weight and substance to Gatsby’s shirts. These outward displays of wealth, these means of disguising/ covering/ dressing his true nature, are in fact the most substantial part of him. The shirts (which Daisy will soon cry ‘stormily’ over) are the foundation upon which he has built his persona.
If we follow this idea further, the fact that he so recklessly dismantles this wall of shirts and hurls them at Daisy could symbolise his willingness to dismantle himself, for Daisy. She evidently picks up on this, on some level, responding with tears. Deep.
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