Without knowledge of a country's ethical cultures, it is impossible to predict whether its tax system will be progressive with regard to income.
Do you agree?
A reasonable answer.
There is no scientific reason why the residents of a country should believe that income should be more or less equally distributed than in any given situation. In the absence of such belief, there is no basis for predicting what the country's income distribution will look like. A straight-forward application of majority rule, assuming that the country's residents believe in it, will not necessarily lead to a more equal income distribution, once we allow for the fact that any large fraction of the community can produce a majority vote for lower and higher taxes respectively for itself and the remaining population. It is thus not necessarily true that a lower-income majority will be able to successfully produce a reduction in its taxes combined with an increase in the taxes of the higher-income minority.