What is your reasoning that says that high income earners should pay more?
The income tax itself is problematic from a Contitutional standpoint. In essence it makes us ALL slaves and the "progressive" tax is even worse as its premise is simply based on envy.
The power to tax is the power to destroy, and we have given our elected congress critters far too much power in this regard. Government revenue sources need to be neutral in regards to individuals as they provide too many opportunities for targeting groups with either incentives or punishments.
It is a social justice position. It is a preference. There is no right or wrong answer. It is important however to not let taxes at the margin get too high or it starts interfering with economic incentives to be productive, and starts killing the goose that lays the golden egg, as it were. It is an empirical question as to just how high a rate and where and when that really starts to be a drag.
As Hillary so elqouently stated in her San Francisco speech a couple of years ago,
"We're going to take things away from you on behalf of the common good." -Hillary Rodham Clinton, 6/28/04
Yep, real 'social justice' there. (s/off)