On Taxation

Few questions:

1. Why shouldn't we move from Income tax to some sort of consumption tax ? As the things stand today Income tax bring a minuscule amount of revenue, owing to exemption to majority of population from paying tax, usually due to pressure from interests group. The advantage of consumption tax, in my view, is that it ameliorates, if not outright eliminates, to a great extent the ability of formation of interest group to pressure for exemption, mostly due to the fact that any exemption requires relatively more rigorous explanation.

2. One of the major reasons given by fiscal conservatives in US to oppose tax hikes on corporations is that the corporations can and will simply pass the hikes to the consumers. Now I can't find any fault with the logic, but shouldn't the same logic hold for the hikes in income taxes also ?