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I was wondering, what would Kant and the categorical imperative say about the following situation?
Person A has made a promise to person B that Person A would not tell of a crime of stealing in a shop that Person B was to commit. However, Person A also happens to know the shopkeeper and has in the past promised the shopkeeper to report any crime that Person A knew was committed in the shop.
Now, we are living in the moment just after B has committed the crime of stealing (unnoticed by others).
The question is now, from a Kantian view, what is the right thing morally for A to do?