Vision: Counting (adding and subtracting, etc.) numbers: can you really afford to have others living at your expense? Solving a mathematical problem is a warning about your spending habits, because you need to find a way out of a difficult situation—and soon!
Depth Psychology: Doing calculations: you can solve your problem if you start using your head.
A slide rule is a sign that you have made a mistake and are looking for help. Sometimes very manipulative people dream about slide rules.
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