I don't have any particular recipe [for developing new proofs] ... It is the reason why doing research is challenging as well as attractive. It's like being lost in a jungle and trying to use all the knowledge that you can gather to come up with some new tricks, and with some luck you might find a way out.
To tax the larger incomes at a higher percentage than the smaller， is to lay a tax on industry and economy； to impose a penalty on people for having worked harder and saved more than their neighbors.
