Income equality is an economic measure of the relative wealth of citizens within a country. Countries with high levels of income equality have large middle classes and relatively small numbers of poor and very poor. This is usually accomplished by income transfers (called taxes and benefits by non economists). Wealthier and more successful people pay higher taxes and the poor, aged, unhealthy, unlucky and sometimes even the lazy get more grants and services. In societies with high income inequality real tax rates are low and the income disparity between the rich and poor is high. Wealthy people keep more of what they earn and the unhealthy, aged and unlucky suffer and die.
We all have our own feelings on what is the best way to organize society and each side has plenty of theory to show why their personal skew has economic merit. But from a stamp collecting point of view the issue is clear. Philately is most popular and thriving in countries with a strong middle class. The top twenty countries in terms of income equality include all the major stamp collecting engines of Scandinavia and Western Europe. And the bottom twenty countries for income in equality (not wealth) include populations of over 500 million people where there is scarcely a single collector. The best seed bed for philately is a mature democracy with a well educated population, a strong middle class, high level of government services, and progressive tax rates on the very wealthy.