Critics of the Federal Income Tax often complain about the complexity

Respond to the following using current literature:

Critics of the Federal Income Tax often complain about the complexity of the tax law ....  In fact, former President Jimmy Carter called our tax law "a disgrace" and Albert Einstein threw up his hands in frustration and said that it was too complicated for him to understand.  One common suggestion to improve our  tax law seems to be that it would be much easier to raise revenue for the Federal government with a national sales tax or a flat income tax with no deductions (based simply on gross income). Please refute these contentions and defend our tax system.  Explain how the Income Tax is designed to achieve multiple goals, i.e., social - political - economic - stimulus - incentive - disincentive objectives ..... and that raising revenue for the government is not the only purpose of the income tax law.