Brazil was the last Western country to abolish slavery, which it did in 1888. As a colonial institution, slavery was present in all regions and in almost all free and freed strata of the population. Emancipation only became an issue in the political sphere when it was raised by the imperial government in the second half of the decade of the 1860s, after the defeat of the Confederacy in the US Civil War and during the war against Paraguay. In 1871, new legislation, despite the initial opposition from slave owners and their political representatives, set up a process of gradual emancipation. By the end of the century, slavery would have disappeared, or would have become residual, without major disruptions to the economy or the land property regime.
By the end of the 1870s, however, popular opposition to slavery, demanding its immediate abolition without any kind of compensation to former slave owners, grew in parliament and as a mass movement. Abolitionist organizations spread across the country during the first half of the 1880s. Stimulated by the direct actions of some of these abolitionist organizations, resistance to slavery intensified and became increasingly a struggle against slavery itself and not only for individual or collective freedom. Incapable of controlling the situation, the imperial government finally passed a law in parliament granting immediate and unconditional abolition on May 13, 1888.
Luis Nicolau Parés
Of the estimated 4.9 million African captives disembarked in Brazil, 70 % were shipped from Central Africa, 24 % from West Africa, and the remaining 6 % from the East Coast of the continent. Despite their diverse political and cultural backgrounds, Africans were classified by slavers with a discrete number of generic categories often referred to as “nations.” The enslaved appropriation of such external labels, like Mina and Angola—distinguishing Western and Central Africans respectively—resulted in the formation of new collective identities. The novel ways of colonial belonging and behavior shaped and expressed themselves as distinct forms of Afro-Brazilian culture when organized around social institutions such as Catholic lay brotherhoods or other African-inspired associative dynamics. Religious practice, including music, language, bodily performance, cooking and dress, became a privileged domain for African cultural production, subsequently irradiating into other secular manifestations. The colonial calundu, concerned with healing and oracular functionalities, greatly influenced by the Bantu-speaking people, coexisted and intermingled with the more ecclesiastical West-African traditions of initiatory ritual dedicated to the worship of multiple deities. Despite common elements of celebration, healing and mediumship, Afro-Brazilian religious pluralism was historically marked by an extraordinary eclecticism. Different local interactions with the hegemonic Iberian Catholicism, Amerindian healing practices and French Spiritism, together with the circulation of people and ideas between Africa and Brazil after the end of the Atlantic slave trade, led to a wide range of regional variation. This heterogeneous Afro-Brazilian religious field, prone to continuous discrimination and selective tolerance by the authorities, is stressed by a discursive contrast between the alleged traditional pure African forms and the mixed syncretic Brazilian ones, all claiming their share of legitimacy and ritual efficiency.
Thomas D. Rogers
The Portuguese took sugarcane from their Atlantic island holdings to Brazil in the first decades of the 16th century, using their model of extensive agriculture and coerced labor to turn their new colony into the world’s largest producer of sugar. From the middle of the 17th century through the 20th century, Brazil faced increasing competition from Caribbean producers. With access to abundant land and forest resources, Brazilian producers generally pursued an extensive production model that made sugarcane’s footprint a large one. Compared to competitors elsewhere, Brazilian farmers were often late in adopting innovations (such as manuring in the 18th century, steam power in the 19th, and synthetic fertilizers in the 20th). With coffee’s growth in the center-south of the country during the middle of the 19th century, sugarcane farming shifted gradually away from enslaved African labor. Labor and production methods shifted at the end of the century with slavery’s abolition and the rise of large new mills, called usinas. The model of steam-powered production, both for railroads carrying cane and for mills grinding it, and a work force largely resident on plantations persisted into the mid-20th century. Rural worker unions were legalized in the 1960s, at the same time that sugar production increased as a result of the Cuban Revolution. A large-scale sugarcane ethanol program in the 1970s also brought upheaval, and growth, to the industry.
Felipe Fernandes Cruz
Aviation has played a unique role in the history of Brazil, beginning with the life of Alberto Santos-Dumont. Most Brazilians consider him to be the true inventor of the airplane over the North American brothers Orville and Wilbur Wright. Born in the province of Minas Gerais in 1873, he became a global celebrity in the early 1900s when he designed, built, and piloted several of his dirigibles and airplanes in Paris. He won major prizes for his aeronautical feats, such as the Deutsch de La Meurthe prize for an aerial circumnavigation of the Eiffel Tower. Santos-Dumont is a beloved national hero in Brazil. The potent symbolism of his life was often invoked in calls for the development of Brazilian aviation.
Throughout the 20th century, aviation was hailed as a technological panacea for Brazil’s problems. Many Brazilians thought its development could boost homegrown industry and technology, and that aviation would in turn enable Brazil to conquer its frontiers by air. The potential to connect vast and often inaccessible territories by air was very attractive to a state with a weak grip on its frontiers. The dictatorial government of Getúlio Vargas, for instance, used propaganda and cultural programs to engender great excitement among Brazilians for the mass development of national aviation.
This notion of frontier conquest by air played a major role in the development of aeronautical technology in Brazil, creating a unique history of frontier expansion and interaction with indigenous peoples. Starting in 1969, Brazil also became a major exporter of airplanes. Originally a state-owned company, the now privatized EMBRAER is one of the world’s largest aircraft manufacturers, selling military, airline and private jet aircraft around the world.
Diogo de Carvalho Cabral
Although it has received less scholarly attention than firearms, microbes, domestic animals and plants, market economy, and statecraft, alphabetic reading and writing was crucial in the European conquest and colonization of the Americas from the late 15th century on. Unlike the agrarian empires the Spaniards encountered in the Andes and the Mexican highlands, the Portuguese frontier advanced upon tribal peoples who relied exclusively on oral language, such as the Tupi of Atlantic Brazil. These were semi-sedentary horticultural villagers whose entire socio-ecology (myths and knowledge, territoriality, subsistence strategies, etc.) was conditioned by the face-to-faceness and fugacity of spoken words. In turn, their Portuguese colonizers—for a while rivaled by the French, who enjoyed short periods of stable settlement through the early 17th century—were urban-based, oceangoing merchants, bureaucrats, soldiers, and religious missionaries whose organization strictly depended on the durability and transferability of written texts. Even if most of the Portuguese who came to Brazil in the 16th century were themselves illiterate, colonization as a social enterprise framed their actions according to prescribed roles set down in writing (both handwriting and printed script). Thus, the Portuguese colonization of Brazilian native lands and human populations can be interpreted from the point of view of the imposition of an alphabetically organized way of life. Two major dimensions of this “letterscaping” can be discerned as to its impact on Amerindian bodies (human and nonhuman) and modes of understanding. Although the 16th century was only the introductory act in that drama, its historical record shows the basic outlines of the alphabetic colonization that would play out through the early 19th century: native decimation and enslavement, territory usurpation by sesmaria grants, forest recovery in former native croplands (then resignified as “virgin forest”), loss of native ecological knowledge not recorded in writing, disempowerment of native cultural attunement to the wild soundscape, among other processes.
The 1922 Modern Art Week is considered the initial landmark of artistic vanguards in Brazil. However, before it was held, Anita Malfatti’s 1917 exhibition, which presented expressionism to Brazilians, and the articles of Oswald de Andrade announcing in the local press the poetry of Mário de Andrade and futurism caused significant polemics and opened the way for renovation. In the middle of the 1920s, the contacts of various artists with European vanguards—especially cubism—and the reinterpretation of the national element and popular culture with the incorporation of this repertoire, with an emphasis on cosmopolitism, established and solidified modernism in various artistic areas. In the 1930s, social commitment, the revalorization of the regional, and adhesion to leftwing ideologies changed the focus of artistic production, leading to the reorganization of groups and the emergence of new protagonists: Patrícia Galvão and Flávio de Carvalho, among others.
The return to classic forms and new experimentalisms marked the 1940s and 1950s, characterized by the reappearance of the sonnet, with Vinicius de Moraes, Cecília Meirelles, Murilo Mendes, and Jorge de Lima; renovations in language that reached a peak with Guimarães Rosa; photomontages by Jorge de Lima. Concrete art and poetry, notably the National Concrete Art Exhibition (1956) and neo-concretism, returning to the strategy of the manifestos and journals of the 1920s, revived the same polemical reception and bitter rivalries.
In the following decade, the revisiting of Oswald de Andrade’s work, especially the idea of anthropophagy, gave a strong impulse to tropicalism, Cinema Novo, and a greater renewal in Brazilian theater, with the staging of O Rei da Vela by the Teatro Oficina group (1967), the culminating point of a fifty-year cycle of artistic vanguards in Brazil.
The population of African descent in Brazil has always maintained vibrant associative communities, whether in the form of mutual aid societies, confraternities, and religious brotherhoods that existed since the time of slavery or in the form of other voluntary associations that appeared later, such as recreational societies, civic centers, literary guilds, musical groups, carnival blocos, and the black press. For Afro-Brazilians, the associative experience throughout the 20th century contributed to a sense of group belonging and a consciousness of a shared identity and experience of racial discrimination. Furthermore, these relationships enabled Afro-Brazilians to begin claiming rights as citizens, protesting against what afflicted them as a community. These joint efforts fueled collective acts of resistance and self-determination that, while evident for centuries, acquired new meanings and manifestations following the abolition of slavery in 1888. Black associations did not limit themselves to denouncing problems or detecting their causes and consequences. They tried to point out ways to overcome them by proposing several solutions: the moral elevation of Afro-Brazilians, which implied a preoccupation with their image in the various sectors where they acted; improving their educational and instructional level; valorizing their race and, by extension, black identity; and emphasizing the need to react to injustices, and even to act politically. However, the main solution was the union of black Brazilians, a sine qua non for this segment of the population to strengthen and thus be able to claim and gain space in society, improve living conditions, and even overcome persistent challenges. Understanding the history of black associative life in Brazil during the 20th century is necessary in order to grasp the struggles and challenges Afro-Brazilians have faced around common interests, particularly since these collective actions are an integral part of the black experience and, in some respects, overlap with it.
In 1863 and 1864, historical and political contradictions in the River Plate region led to civil war in Uruguay, creating tensions with neighboring nations in the region. The Brazilian government intervened both politically and militarily in Uruguay to address the interests of ranchers in its province of Rio Grande do Sul, to distract the attention of the Brazilian citizens from domestic problems, and to preserve the political influence of the Empire of Brazil on Uruguay. This action by the Empire clashed with the new Paraguayan policy of political interference in the River Plate region and resulted in the declaration of war against Brazil by Paraguayan dictator Francisco Solano López. This conflict broadened into the Paraguayan War.
As the world’s fifth most populous nation and by far the largest Portuguese-speaking country, Brazil possesses a massive media market. Despite factors boosting demand for homegrown audiovisual content, the fortunes of the country’s film industry—prized as a means of expressing national identity and as a testament to technological modernity—have fluctuated over time. Historically, the sector has struggled in the face of competition from imported cinema, especially Hollywood product, which has dominated Brazilian screens since the mid-1910s. Nevertheless, Brazilian cinema has attracted mass audiences at home and won critical acclaim abroad, though not always with the same films. The humorous chanchadas (musical comedies) that characterized the industry from the 1930s through the 1950s were tailor-made for domestic audiences, but gained little traction internationally. By contrast, the politically charged and stylistically inventive films of the Cinema Novo movement attracted the attention of European and US critics, but held limited appeal for most Brazilian spectators. After Cinema Novo, few works of Brazilian cinema circulated in international markets until a series of gritty crime-themed films like City of God (2002) and Elite Squad (2007) reached global screens at the turn of the 21st century, bolstered by state incentives for private investment in film production. While this fare was also popular domestically, present-day Brazilian audiences often prefer romantic comedies, biopics, and religiously-themed films. These trends in Brazilian cinema have responded dynamically to the tastes and expectations of both national and international audiences. Onscreen representations create enduring images of the nation that circulate at home and abroad, while everyday practices of moviegoing forge an evolving realm of shared experience.
José Jobson Arruda
The development of the Brazilian economy during the colonial period resulted from foreign inducements exercised by Portuguese colonialists under the auspices of the Portuguese Crown. Over the course of three centuries, responsibility for Brazil’s economic destiny was gradually transferred to Luso-Brazilians, a process by which both the flow and accumulation of income became naturally internalized. This topic must necessarily be contextualized within a decades-long process of historiographical confrontation in which distinct analytical perspectives have sought to assert themselves. Some arguments are linked to the label of the old colonial system (Antigo Sistema Colonial, or ASC) and others to the old regime in the tropics (Antigo Regime nos Trópicos, or ART). While both schools recognize the primacy of slavery in determining the character of colonial society, the former emphasizes colonial identity and the exploitative status that entailed, while the latter focuses on the empire and the endogenous accumulation of wealth.
Despite the friction between these hegemonic currents since the 1980s, a third analytical perspective is possible that while incorporating elements present in the two established outlooks also rejects the exceedingly long periodization and calcified three-century focus they share. This different strain of scholarship distinguishes between specific moments in colonial economic development during which external and internal accumulation fueled one or the other, serving as complementary forces responsible for the gross and per capita growth of the colonial economy, as well as granting Brazil the profile of a modern colony.
Herbert S. Klein and Francisco Vidal Luna
The 20th century represents a crucial period in Brazil’s economic history, when an agrarian, rural-dominated society became an urban, industrialized country with a complex financial sector and a large service sector. This economic transformation fueled by coffee exports led to profound demographic and social changes as millions of European and Asian immigrants were integrated into Brazilian society, followed by a massive shift of native-born migrants from the northeast to the dynamic southeast of Brazil, particularly for the state of São Paulo, which became the richest, most industrialized, and most populous state of the nation. The second half of the 20th century saw the creation of a modern industrial sector and the modernization of national agriculture, which in the 21st century made Brazil one of the most important producers of grain and animal protein in the world.
Thiago Lima Nicodemo, Pedro Afonso Cristovão dos Santos, and Mateus Henrique de Faria Pereira
Brazilian historiography in the 19th century stands for a variety of practices and ways of doing history. In the beginning of the century, the writing of history assumed a specific color after the arrival of the Portuguese Court in 1808, who were escaping the invasion of Portugal by Napoleonic troops. After political independence from Portugal (1822), this writing had to deal with the questions that occupied the minds of its authors, people mostly close to or part of the political elite of the country. Forging a nationality through history, dealing with the tensions between local affiliations and the nation-state, placing indigenous and African peoples in the historical narrative, combining an exemplary history with future-oriented thinking, and using history for international relations issues (such as boundaries disputes) were among the motivations and preoccupations involved in that work. Underlying it all, the myriad ways of writing history in the 19th century had to do with the ways the authors circulated among a world of public archives in the making, personal archives available through certain connections, booksellers, publishers, oral informants, and a changing community of readers and critics that were conforming and disputing rules of acceptability as to what could be considered a work of history. Thinking about the Brazilian historiography of the 1800s as a way of combining practices of archiving, reading, copying, writing, and evaluating can help us understand the remarkable variety of histories and historiographical works written in the period.
João Paulo Pimenta
Stemming from an accelerated and tumultuous process unleashed by European wars in the first decade of the 19th century, Brazil and Portugal split politically in 1822. In a sense, Brazil’s independence reflects a number of peculiar characteristics within the context of the time due, in part, to three centuries of Portuguese colonization and to changes within the colonial system beginning in the second half of the 1700s. In other ways, however, Brazilian independence is linked to external events like the French Revolution, the independence of Haiti, and, above all, the wars of independence in Spanish America. The most profound and lasting consequences of the break with Portugal were the emergence of a Brazilian state and nation that until that point did not exist and that was consolidated over the course of the nineteenth century, as well as the nationalization of certain colonial institutions that were partially maintained. Historiography and national memory would later imbue independence with supreme importance as the foundational moment of the nation such that it has become a recurring theme in historical studies of Brazil.
Since its establishment in 1889, the history of the Brazilian republic was marked by the centrality of the armed forces, particularly the army, in political life. But between 1964 and 1985, the military was in direct command of the state, imposing indirectly elected generals as president. After overthrowing the reformist center-left government of João Goulart on March 31, 1964, the military installed a tutelary authoritarian regime to control civil society and the political system, serving as a political model for similar regimes in Latin America during the Cold War.
The military passed arbitrary laws and severely repressed left-wing political groups and social movements while also seeking to accelerate capitalist development and the “national integration” of Brazil’s vast territory. They intended to modernize Brazilian industry and carry out bold infrastructure projects. On the other hand, they faced strong opposition from civil society, led by political groups, artists, intellectuals, and press outlets of diverse ideological backgrounds (Marxists, liberals, socialists, and progressive Catholics). These groups were divided between total refusal to negotiate with the military and critical adherence to the policies of the generals’ governments, composing a complex relationship between society and the state.
Understanding the role of the military regime in Brazilian history requires a combination of historical research and historiographic criticism in light of the disputes over memory that continue to divide social and political actors.
Rodrigo Patto Sá Motta
Recently Brazil reached the mark of eight million university students, which represents around 4 percent of the population. Although this level is less than those in developed countries, it signifies an advance in relation to the country’s starting point.
Unlike Spain, the Portuguese Empire did not create university institutions in its colonies. Following the Independence of Brazil in 1822, the new governing elite established some higher-level courses (initially medicine, law, and engineering), but these functioned in isolation, in other words, university institutions were not created. The first universities emerged only in the 1920s and were regulated during the Getúlio Vargas administration (1931). Since then, higher-level education has been the object of greater public attention—as well as political conflicts—due to both its role in development projects and its capacity to produce leaders. Between the 1940s and 1960s, university students became a relevant political force, having engaged in debates for university reform and also in favor of social changes, contributing to the process of political radicalization abruptly ended by the 1964 military coup. The dictatorship led by the military implemented an authoritarian modernization of the universities, repressing and purging the “undesirables” at the same time that it increased investment in research and graduate studies. The results were paradoxical, since although the dictatorship created a better structured university system, it was a more authoritarian and socially elitist one.
The first post-dictatorial governments maintained the university structure inherited from the previous period, but they deteriorated due to a lack of public resources caused by hyperinflation and also by the intention of reducing public expenditure on higher education.
The country managed to improve its higher-level institutions during the 20th century, which became strategic spaces for political battles and, for this reason, targets of constant state intervention. Despite the reforms and the expansion, universities were marked by elitism and social inequality, like Brazilian society itself, problems that only recently have started to be addressed. Only in the 21st century did Brazilian universities undergo a new expansionist phase, led by the center-left Brazilian governments which, in addition to expanding the public system, also invested in the inclusion of social sectors that previously had no access to higher education. It appears that this process may be interrupted, thanks to the “right turn” experienced by Brazil since 2016–2018.
José Luiz de Andrade Franco and José Augusto Drummond
The rich variety of the tropical ecosystems and wildlife native to the current territory of Brazil has captured the attention of several groups of observers since the early 1800s. Wildlife and landscapes in particular generated a continuous stream of appreciation of their uniqueness and concern about their integrity. This perception affected government officials and foreign traveling naturalists of the 19th century, when dozens of French, German, Austrian, English, Belgians and North American naturalists traversed the immense territory of the former Portuguese colony that had been virtually closed to trained scientists. Throughout the 20th century, newly trained Brazilian scientists and again foreign scientists, besides government officials and activist citizens, continued to explore species, ecosystems, and landscapes of what now recognized as the largest tropical country of the world. More recently, the growing amount of information about the global distribution of biodiversity placed Brazil at the top of the ranking, as a truly “megadiverse” country. As a consequence, Brazil has engaged, through environmental non-governmental organizations (NGOs), government agencies, and foreign and locally trained scientists, in a remarkable series of successful projects aimed at the identification and protection of endangered species. The country has only recently built a cadre of wildlife and ecological scientists trained to initiate and manage these types of projects. Despite the fact that these efforts are still far from being a priority in terms of its national environmental policies, Brazil has been quite active and successful in the protection of some of its most endangered animal species and their habitats.
Four elements of Brazil’s identity—its large size, its self-perception as part of the Western world, its vulnerability to European intervention and to the changing world economy, and its success in defending itself through diplomacy—have all contributed to shaping its aspirations in the international domain. Participation in the councils of the great powers became a means by which Brazilian diplomats could pursue a world order that was more favorable to its interests.
But even though domestic aspirations and foreign perceptions have held out the prospect for Brazil becoming a major power, it has lacked the capabilities—particularly on the military and economic dimensions—to pursue a traditional path to greatness. Militarily, Brazil has been only episodically consequential, and less so as we approach the present. Given South America’s remoteness from the geopolitical centers of global conflict, Brazil has faced little pressure to improve its modest security capabilities beyond what was necessary to fend off its smaller neighbors. Brazil’s efforts to advance through partnerships with other states have been hobbled by a historical reluctance to pool its sovereignty. In addition, turbulent domestic politics or major economic crises have periodically undermined Brazil’s credibility and capabilities, interrupting its rise.
How has Brazil sought to overcome the gap between its ambitions and its capabilities? Brazil was a prominent exponent of the practice of ‘soft power’. It positioned itself internationally as a proponent of equality among nations, international law, and the peaceful resolution of conflicts. To this, Brazil has added a formidable cultural output and most recently, democracy, prosperity and social inclusion. This is an attractive package, particularly for other developing countries who want to find a similar status. This chapter follows Brazil’s attempts in the 20th century and up through President Dilma Rousseff to parlay this approach into a say in shaping the rules governing the international order.
Bernardo Buarque de Hollanda
Football appeared in Brazil in the end of the 19th century, among a favorable environment for the practice of English sports. These sports were initially practiced not professionally by English migrants and young students of Law, Engineering, and Medicine. Fluminense was the first club from Rio de Janeiro, at that time the capital of the country, to be dedicated exclusively to practice football. In the beginning, football represented nobility for the local elite. The social profile of people who attended matches at Fluminense’s field was very near to that of the players, be it for family reasons, friendship, or other motivations. Young women who went there desired to see their distinguished idols, and from this practice many relationships started. While this idyllic image of the past was produced, a historical point of view can notice a decisive enhancement in social segments interested in football. In the decade of 1910, a collective enthusiasm arose for football, mainly due to the fact that it was easy to practice and watch football in any kind of open space. This allowed it to spread out of clubs and the National Team. Far from the spatial and economic restriction of performance arts, football could be practiced and watched freely, in most diverse situations. The clubs’ lack of structure to allocate players and fans contributed in making football a popular game, since they needed to seek public spaces to practice. At this point, the club that opposed to Fluminense has been Flamengo, which until then was not more than a regatta club. When it opened a football department, it practiced in open fields near the beaches. Many passersby started to look out their training and matches, and some of them adopted Flamengo as their club even if not participating of its internal sphere. The players became idols, first in the neighborhood and then in the whole city. This encouraged the talk about football in bars and cafés, with reflections on the increasing number of people to attend matches. Historian Leonardo Pereira says that in a few years football has become a mania. The making of the first national team to dispute friendly matches against England and Argentina has also stimulated football’s repercussion. Noticing public interest over matches with teams from different cities or countries, sports press left its poor attitude about football and began to carefully pay attention to this kind of rivalry and the consequent emotions each fan is able to express for his team, especially the National Team.
Luiz Bernardo Pericás
The cangaço was a social phenomenon related to rural banditry in the backlands of the Brazilian Northeast (an area referred to as the sertão). Beginning in the nineteenth century, the cangaço reached its peak with the actions of Virgulino Ferreira, popularly known as Lampião, the most important and emblematic leader of these outlaws, during the 1920s and 1930s. Its demise came with the start of the dictatorial Estado Novo regime in 1937. The cangaço received widespread coverage in the local press and was amply depicted in the visual arts, literature, and cinema, enduring as one of the most distinctive and controversial subjects in Brazilian cultural history.
Matthias Röhrig Assunção
Capoeira is a martial art that developed from combat games enslaved Africans brought to Brazil. It is systematically documented since the beginning of the 19th century in Rio de Janeiro and later in other port cities. During the 19th century capoeira was increasingly practiced by the poor free people, black and of mixed ancestry, and also by white immigrants. Capoeira gangs controlled their territories against intruders and allied with political parties until the Republican purge of 1890. Capoeira survived best in Bahia, where it remained more associated with other forms of Afro-Brazilian culture and acquired many of its features still extant in present-day capoeira. From the 1930s onward, capoeira masters such as Bimba and Pastinha modernized capoeira, leading to the emergence of the Regional and Angola styles. Bahian capoeiristas migrated to Rio de Janeiro and São Paulo in search of better opportunities during the 1950–1970s. There they and their students developed what later became known as “Contemporary capoeira” (Capoeira Contemporânea) which is the most practiced style today. Capoeira was and is practiced in various ways: as a friendly game or as a fight, as a combat sport, or as an Afro-Brazilian cultural activity. Since the 1980s, capoeira has undergone a process of globalization and is now practiced in many countries around the world. Capoeira is the only martial art of the African Diaspora that is known and practiced worldwide. Writing on Capoeira has rapidly grown in a number of disciplines, leading to the constitution of its own interdisciplinary field of study.