Rio de Janeiro — This vast nation, which takes a big step from military rule toward democracy this week, is a troubled paradox: In many ways it has left the third world far behind, but it still wallows in much third world backwardness.
Brazil's ''economic miracle'' has edged it into eighth place among the world's economic giants - the first tropical land to become an economic power of consequence. Yet today Brazil is saddled with huge international debts and one-third of its people have never benefited from its attempt to break out of poverty.
In a sense, Brazil is two nations - one well on the road to development, the other remaining behind, an albatross around the neck of the first.
Brazil is the world's second-largest exporter of foodstuffs. It is still the leading coffee producer, and it has recently become the world's largest sugar producer and second-largest soybean producer, a major factor in the world grain trade. Industrial exports are beginning to rival Western Europe as Brazilian-made products take the lead in some markets in Africa, the Middle East , and Latin America.
''Made in Brazil'' signs on cars, trucks, armored vehicles, ships, and airplanes are familiar sights in the industrialized world as well.
The people of this industrialized Brazil have a lifestyle akin to, say, citizens of the Benelux countries of Western Europe. Social mobility permits more and more Brazilians to enjoy the fruits of this expanding economy. Per capita annual income is more than $2,000 (US) - and growing. The people of this Brazil represent a growing legion of educated, trained workers. Engineers and technicians who travel abroad think of Brazil as a vital power on the world scene, and see themselves as part of the so-called first world.
But the other Brazil is more like India than Western Europe. Its impoverished millions - a third of Brazil's 125 million people - live outside Brazil's ultra-modern cities and far away from the country's growing consumerism. Lacking housing, education, jobs - in short, lacking opportunity - their daily concern is simply to get enough to eat, to get by.
Their plight mortgages Brazil's future every bit as much as does the nation's whopping $80 billion foreign debt.
''The deep, lingering echoes of this third world situation cannot be ignored, '' says Helio Barbosa da Sousa, an economist with the Banco do Brazil.
Austregesilo de Athayde, one of Brazil's most renowned thinkers, agrees. ''The past is still with us,'' he warns.
Indeed it is. Here in Rio de Janeiro, once Brasil's capital and still its major playground, the well-to-do and ladder-climbing middle class fill the cafes and stores. They virtually ignore the masses of impoverished Brazilians living in slums behind the hills that partially ring this city.
As many as 1.5 million of Rio's 4 million people lack proper housing, sufficient food, educational opportunity, or rudimentary social services. And their numbers are growing as the population spiral continues - Brazil's birth rate is 2.6 percent a year and poor rural people continue to migrate here and to other cities looking for work.
There are other regions of the backward Brazil - in the expanding industrial southland and in the impoverished agricultural northeast of the country. The contrast between these two Brazils is in some measure as mighty as that between industrial Chicago and rural Haiti.
Brazil's government planners are acutely aware of the contrasts. Political candidates noted them as well in the campaign leading up to this week's election.
Government planners say they hope the economic miracle that propelled Brazil forward industrially will somehow gradually pull along many of the impoverished millions. It has already helped, to a degree, some of the poor. There is no mistaking Brazil's social mobility in contrast to much of the third world.
But too few of the 50 million-or-so ''third world'' Brazilians have been able to grab even the bottom rung of the ladder of economic advances.
Still Brazil is advancing by dint of hard work, thinking big, utilizing its many though not unlimited resources, and employing a sense of national confidence that is uniquely Brazilian. It may not be a ''first world'' country yet, but it is trying hard.
Brazilians do work hard. This is evident in the so-called economic miracle. Worker productivity is higher here than in many other third world nations - 40 percent higher than Mexico, for example. The Ministry of Labor says Brazilian productivity is even ''higher than in the United States.''
The Brazilian capacity for thinking big should not be underestimated. There is a sense of gigantism here, perhaps inspired by the fact that Brazil is, land-wise, the fifth-largest nation in the world.
But it goes deeper than that. Brazilians have a sense of national identity and of national destiny. They also have an almost unbounded sense of confidence about themselves. They tend to have the idea that nothing is impossible. ''God is a Brazilian,'' according to a popular refrain.
''There should be no mistaking this factor,'' comments a longtime United States resident married to a Brazilian. ''It is the frontier of the American West all over again, and it is what distinguishes Brazil from all the rest of Latin America and the third world.''
He continues: ''Other third world people live and complain about their plight but often do little about it. They tend to blame the United States or something other than themselves for their plight.
''Brazil is different. Oh, to be sure, you hear complaints here. But they don't end there. Brazilians do something about the trouble and usually end up solving it fairly well.''
Take energy, for instance. Brazil is oil-short. Although most everyone is convinced there is plenty of oil somewehere in this vast realm, it so far has not been found. Brazil instead has to import 75 percent of its petroleum needs, to the tune of $10 billion or so a year.
Instead of wringing their hands, Brazilians have tackled the problem imaginatively. The percent of petroleum needed to run industry has dropped considerably in recent years. More oil has been found, but the key factor in the energy picture here is the push toward hydroelectric power, capped last week with dedication of the Itaipu hydroelectric complex on the Parana River.
When fully operational later in this decade, the $12 billion Itaipu project will provide the total energy needs for Brazil's industrial southland, the section of the country that generates two-thirds of Brazil's total gross domestic product of $270 billion annually.
Then there is gasohol. Brazilians are pioneers in this field. More than 70 percent of all Brazilian vehicles now are powered with this mix of gasoline and alcohol, the latter coming from a variety of agricultural products that are cultivated primarily for this use.
Problem-solving of this sort is typical of Brazilians.
Brazil's sheer size, its growing internal market, its ability to attract public and private investment from overseas, as well as the ability to generate national investment are all factors.
But underlying it all is that sense of confidence that anything is possible, a frontier mentality with a unique Brazilian twist to it.
Brazilians call this jeito - a word suggesting improvisation, sometimes inspiration, or a style of solving problems.
Sometimes the solutions are only temporary. But they spring from that unique Brazilian enthusiasm that gets things done - and helps explain the movement from the third world toward the industrialized first world.
There are few Brazilians who doubt that the other foot can be lifted from the backwardness that would keep a third of the population in poverty, but as yet that way is not clear.
''But we will find a way,'' comments Antonio Delfim Netto, Brazil's planning minister, who as much as anyone is responsible for guiding Brazil's economic leap forward.''We must find that way,'' he adds.