NICARAGUA

Sometimes in Managua, everything blurs but the people. Shattered by an earthquake in 1972, the downtown of Nicaragua's capital was never rebuilt. Today Managua is a centerless city - a curious, dusty Latin American L.A. but without freeways, and with few swimming pools.

Much of what is called Managua is a series of suburbs strung together by roads. The roads seem to be punctuated with shopping centers and progressions of revolutionary billboards. Residential areas, usually tucked away on obscure side roads, are hidden from highway traffic.

Seen through car windows on a blazing hot afternoon, Managua looks like an indistinct mass of written slogans, exhortations, open pickup trucks teeming with people, slightly run-down supermarkets, nondescript restaurants, and stretches of amorphous wooden buildings.

But always, something catches the eye, some moment of human contact takes place that reminds you of how overwhelmingly small-town Managuans are:

The policewoman who calls you ''amorcito'' (little love) as she asks for your papers at a checkpoint. Street children who beg but want to chat even if they are refused money. The innumerable friends who honk their horns as they pass on the road. All these commonplace incidents testify that it takes more than earthquakes, barren landscapes, revolution, and war to overcome Nicaraguans' relentless drive to communicate with one another.

Playful, sometimes skeptical, often affectionate banter is heard wherever Nicaraguans congregate. Their conversations are colored by their history - which includes more than 400 years of war, earthquakes, and social injustice. Nicaraguans express a humor that acknowledges the difficult conditions of life here. They accept difficulty as inevitable, but defiantly show that they are nobody's fools. They know humbug, hypocrisy, and injustice when they see it.

Nicaraguan humor is part jive, part street smarts. It is also expressive ironic shrugs and knowing insinuations. And yet it is essentially tolerant, rarely nasty, not aggressive, more interested in entertaining the listener than in cutting him down to size.

No matter how problematic life becomes, Nicaraguans will not be browbeaten. They will fall back on the small pleasures, like talking and joking with neighbors.

It is a humor of the oppressed, but not of the servile. Class differences are strong in Nicaragua. Social oppression has occurred since the Spanish conquerors enslaved the local Indian population. But compared with El Salvador and Guatemala, Nicaragua's rich have never been as rich, nor its poor as destitute.

In a way, the strong landholding peasant class has set the country's social tone. Even before the revolution that put the Sandinistas in power in 1979, Nicaraguans tended to be relatively direct, down to earth, and egalitarian. Domestic servants in Nicaragua were never as servile or self-abasing, as passively accepting of an employer's injustice as those in most other Central American nations. At the same time, the nation's aristocratic families were likely to affect a saltier humor than the El Salvador's 14 ''first families,'' who showed a haughty sophistication.

But Nicaragua's aristocracy doesn't need elaborate manners. Like most of their countrymen from wealthy oligarch down to migrant worker, they have an innate dignity. And although they are chatty and sociable, they do not match the stereotype of Latin Americans as voluble, wildly gesticulating people.

Like many of their Indian ancestors, Nicaraguans have a certain reserve. Market vendors in Managua lack the aggressiveness of their Caribbean counterparts. Crowded Managuan restaurants generally don't reach the noise level of cafes in the Dominican Republic or Puerto Rico. Nicaraguans would find excessive smiling and loud or gushy social manners undignified.

Nicaraguans' friendly, rough-and-ready ways bring to mind the Old West of the United States. Some of their Central American neighbors view the Nicaraguans in much the same way East Coast Americans viewed the oldtime westerners. The polite Costa Ricans, in particular, tend to think Nicaraguans are rough-hewn. But North Americans and Europeans often find them refreshingly blunt and honest - qualities that many of these foreigners do not consider Latin.

Nicaraguans are also known for their sensitive and introspective streak. The country is the birthplace of Ruben Darrio, perhaps Latin America's best-known poet, and poetry remains a national passion. Schoolchildren and partygoers spend hours reciting it, and the most surprising range of people - gruff Army officers , taxi drivers, the pool boy at the Intercontinental Hotel - write it.

Sometimes it seems that every second or third Nicaraguan writes verse. Nicaragua - which until the Sandinista revolution was widely considered just another banana republic - produces poetry that can hold its head up to the best of what is written in Mexico, Chile, and Argentina.

Another outlet for Nicaraguan sensitivity is painting. Observers of the Latin arts scene consider Nicaraguan artists to be by far the best in Central America. Some of their work has a freshness and a sensitivity that makes for art that is not only ''good'' but also good to look at.

Despite dictatorships, earthquakes, a revolution, and today's regional tensions, political uncertainty, and warfare, the Nicaraguan character remains relatively unchanged.

Life is difficult for most Nicaraguans. It always has been. But many more Nicaraguans know how to read and write than before the revolution. Health care is better. Many of Managua's slums now have electricity and running water. Almost as important is the sense that the government is no longer the property of the rich. But shortages of food, clothing, and basic household goods abound. Supermarket lines are interminable. Military and neighborhood guard duties are irksome burdens. And many families know the loss of loved ones in the growing war here. Political repression, while not as strong as under the dictatorship of Anastasio Somoza Debayle, exists.

Nicaraguans deal with these difficulties as they always have. They use their humor as weapon and consolation. Intelligent and critical, they are curiously resistant to propaganda of both the political left and right.

What does the average Nicaraguan feel about his life? What does he feel about his government? It's hard to say. Many observers underrate the complexity of Nicaraguan reactions. A person who complains bitterly of long food lines can also be an enthusiastic Sandinista supporter. And many of those shouting for ''people's power'' at mass rallies are antigovernment at heart. But most close observers seem to feel that the population breaks down into thirds: one-third militant pro-Sandanista, one-third anti-Sandinista, and one-third in the middle.