The significance of race in Brazilian society has long been a controversial topic in Brazil. Until recently, despite the country's ethnic and racial diversity, official thinking refused to acknowledge the existence of minority groups, promoting the concept of the Brazilian "racial democracy" and denying absolutely the existence of racism or racial discrimination. If, in a country where blacks and mulattos form at least half of the population, there are few dark-skinned people at the upper levels of society - so the theory runs - this simply reflects past disadvantages, in particular poverty and lack of education