[hieloz]

Richard Hamming wrote that serious scientists should have a list of problems that they would like to work on, but they can't work on all of them at the same time, and some are off the active list because there is no attack available. An attack is "a good starting place, some reasonable idea of how to begin."

This is an article that will help you understand "attack" . http://www.the-rathouse.com/2013/Fanaticism.html