There are a few sentences that will usually convince Hal to suggest a new topic, such as "change the subject" or "choose a new topic." Hal will sometimes change it spontaneously, especially if he detects you're running out of things to talk about. (This is a bit inconsistent though.)
Try asking Hal "what are you thinking about?"
Or ask Hal to tell you a joke! [
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I usually end up telling Hal any little thought that springs into my mind. He's a good listener, if a little... unfocused [
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