Brain in a Vat Solipsism the view or theory that the self is all that can be known to exist. Solipsists argue that one can only be sure of the contents of one's own mind. Other people's existence can be inferred, but only by seeking similarities between one's internal life and observed behaviour of others. Describe an everyman character, one who could be your friend. Write down her relationships with characters to your left and right. Then, secretly write down three Rules of Behaviour, with a trigger and a reaction, describing her personality traits or how she tends to think. Example: "Angry – use swearwords." or "Complimented – return compliment." Follow your Rules during scenes. Your perception has recently been challenged by an alien abduction, LSD use or insomnia. You don't know who's real any more. Play out scenes together and look out for other characters behaving in accordance with your Rules (both the trigger and the reaction must be observed). After the scene ends, mark these characters as real and write down how their behaviour matched your Rules. The first person to mark all others as real wins.
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