The flat tax fundamentally misunderstands how value works. Ask any economist, or indeed anyone who's taken a college economics course, and they'll tell you that the more of something you have, the less each bit is worth to you. This applies to money as well. Applying a flat tax rate actually taxes the rich *less* then the poor in terms of the actual value they get from their money. For illustration purposes, let's have an extreme example. If you have just $20 to your name, you can afford to eat (badly) for probably about a week. If I take half of your $20, you can now only afford to eat for a few days. The quality of your life has decreased dramatically. If you have $2 million dollars, you're in no danger of starving, and you can buy yourself a nice house. If I take half your $2 million, you're still in no danger of starving, and you can still buy yourself a pretty nice house. Your quality of life has been, at worst, marginally impacted.