the reasons or causes relating to something. I refuse to discuss the whys and wherefores of my decision. It's final. Bob doesn't know the whys and wherefores of his contract. He just knows that it means he will get a lot of money when he finishes the work.
All the underlying causes and reasons, as in She went into the whys and wherefores of the adoption agency's rules and procedures. This idiom today is a redundancy since why and wherefore mean the same thing. Formerly, however, why indicated the reason for something and wherefore how it came to be. [c. 1600]