Should the tax system be used to level out differences by taking from the rich and giving to the poor?

Should those on low incomes be taxed at all or does everyone need to contribute to society? if the wealthy lose a huge amount in taxes, will this be a disincentive? why make money if the taxman is gonig to take it from you? should married couples and those with children pay less tax? or would it be better to have only indirect taxation - collected when you spend money e.g. on petrol, clothes, services, etc ?