A man walked into a library and asked the librarian, "Do you have any books on Pavlov's dogs and Schrödinger's cat?"
The librarian replied, "It rings a bell, but I'm not sure if it's here or not."
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Wait. I think I have a little idea of what ya talking about 😂
I know about Pavlov's dog that whenever it ears the bell rings, it knows food is around...