High marginal tax rates are bad only if you assume that the highest earners are most productive. But are they? Don't forget that wealth is also self-perpetuating. If I earned $1 million - whether by hard work, or by luck - then I could live comfortably off the interest for the rest of my life. In terms of satisfying my basic needs, I would have zero incentive to continue being productive. If I live off the interest, am I somehow being productive by proxy of my investment? That's another question.