I think I tends to lucid dream more when I've messed with my usual sleeping patterns a bit. So, for me, it's the late night rather than crowds that is likely to cause a lucid dream. If I sleep over and stay up chatting, the cause is the same.
Being around crowds of people all day (as a teacher) I don't see a great connection. In fact, I'm possibly slightly more likely to LD on a weekend or holiday.
Still, everyone is different. Maybe crowds energise you in such a way that you LD.
"A dream is a question, not an answer."
(Therapist and dreamworker Strephon Kaplan
Williams)
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