Coffee and Creamer
Max puts creamer into his coffee and it becomes cloudy. The symbol is that Max's brain is clouded just like the coffee. That it is mixed up and not completely formed together.
Multiple Locks
Max has multiple locks on his door to his apartment. This arrangement symbolizes that he is highly paranoid about his privacy being invaded by the outside world. It also denotes the many secrets that he is keeping.
Peephole
Max has a peephole on his door that he peers out of to see who is coming and going in the hallway. The symbol is that he has become so isolated that he doesn't even want to come in contact with anyone for fear of having to interact with them.
Smoke
Lenny talks to Max about the golden ration and how it is found everywhere in nature. We next see Lenny exhale smoke from his cigarette and it forms the golden ratio in the air. It's a symbol that numbers exist in everything in nature.
Go
Max plays Go with Sol throughout the film. It's a game that symbolizes the chaos and infinite nature within life and nature that cannot be figured out.
