I don't particularly care why Crick and Watson did what they did - it could have been pride, a feeling of duty, idle curiosity or even an entry requirement of the local Badger Baiting and Bear Tossing Society.
Similarly, the frame of mind of Newton as he put the finishing touches to Principia Mathematica isn't at all relevant to its content. He may well have considered himself to be a large, unfeathered chicken at the time.