A progressive income tax always raise more revenue than a proportional income tax. Do you agree or disagree?

It is not necessary that a progressive income tax always
results in greater total revenue than a uniform proportional tax. The total revenue is
dependent on several factors including the basic rates of tax. Uniform rate of tax can
be very low or very high. Also the the difference in tax rates applicable at low and
high levels in a progressive tax system may be small big. total revenue collected will
be very much depend on the exact tax rates applicable.

The
total revenue is also affected by the total income earned, and the distribution of
income according to high or low income categories. The tax rates applicable influence
the motivation of people to earn more money. A progressive income tax rate that is too
high may discourage people from undertaking many types of business activities, where the
profit margin is low or the risks are high. This may result reducing the total income
over which the tax is collected at a rate that is higher than the rate of increase of
tax rate. This will result in reduction of total revenue with increasing tax
rates.

Finally, higher tax rates encourage people to adopt
legal and not so legal means of avoiding tax. This again tends to reduce the the total
base of income over which the tax is collected. This may also cause the revenue to fall
as the rates of taxes increase.

In summary we can say that
the absolute rates of taxes as well as the difference in rates of taxes for different
levels of income do not bear a direct relationship with the total tax revenue.
Governments need to pay careful attention to the effect of income tax rate on motivation
of people in engaging in different types of business and in income tax avoidance
practices to arrive at optimum tax rates.