With the "taxes harm growth" and Laffer curve arguments undercut by research such as this, Republicans have fallen back on the argument that it's unfair to take income away from those who earn it. But that presumes that the system allocates income fairly, a claim that is hard to swallow given how much financial executives are paid relative to their contribution to the productive process (to name just one example). There's nothing unfair about using taxes to "clawback" misdirected income, and it won't harm growth to send income where it should have gone in the first place.It's called taxing economic rent.
Read it at Economist's View
"High Tax Rates Won't Slow Growth"
by Mark Thoma
Should we be taxing at all in a stagnant economy?
Yes. Inequality and lack of fairness are socially and economically detrimental. When inequality grows due to both rent-seeking behavior and lack of fairness, e.g., a tilted playing field, then distributional maleffects have to be addressed fiscally by taxing away rents while increasing transfers where most needed and spending that is stimulative.
One purpose of taxation is to discourage behaviors that are detrimental, e.g., socially, environmentally, or economically, and that is still needed even when the sectoral balance approach and functional finance indicate larger fiscal deficit is needed to offset increased non-government saving desire.