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Saturday, June 28, 2025

Indentured servitude in British America

An 18th-century indentured servitude contract

Indentured servitude in British America was the prominent system of labor in the British American colonies until it was eventually supplanted by slavery. During its time, the system was so prominent that more than half of all immigrants to British colonies south of New England were white servants, and that nearly half of total white immigration to the Thirteen Colonies came under indenture. By the beginning of the American Revolutionary War in 1775, only 2 to 3 percent of the colonial labor force was composed of indentured servants.

The consensus view among economic historians and economists is that indentured servitude became popular in the Thirteen Colonies in the seventeenth century because of a large demand for labor there, coupled with labor surpluses in Europe and high costs of transatlantic transportation beyond the means of European workers. Between the 1630s and the American Revolution, one-half to two-thirds of white immigrants to the Thirteen Colonies arrived under indentures. Half a million Europeans, mostly young men, also went to the Caribbean under indenture to work on plantations. Fraud and sometimes even force were widely used as methods of recruitment. A debt peonage system similar to indenture was also used in southern New England and Long Island to control and assimilate Native Americans from the 1600s through the American Revolution.

Indentured servitude continued in North America into the early 20th century, but the number of indentured servants declined over time. Although experts do not agree on the causes of the decline, possible factors for the American colonies include changes in the labor market and the legal system that made it cheaper and less risky for an employer to hire African slave labor or paid employees, or made indentures unlawful; increased affordability of travel to North America that made immigrants less likely to rely on indentures to pay travel costs; and effects of the American Revolution, particularly on immigration from Britain. In the Caribbean, the number of indentured servants from Europe began to decline in the 17th century as Europeans became aware of the cruelty of plantation masters and the high death rate of servants, largely due to tropical disease. After the British Empire ended slavery in 1833, plantation owners returned to indentured servitude for labor, with most servants coming from India, until the British government prohibited the practice in 1917.

North America

Between one-half and two-thirds of European immigrants to the Thirteen Colonies between the 1630s and the American Revolution came under indentures. The practice was sufficiently common that the Habeas Corpus Act 1679, in part, prevented imprisonments overseas; it also made provisions for those with existing transportation contracts and those "praying to be transported" in lieu of remaining in prison upon conviction. In any case, while half the European immigrants to the Thirteen Colonies had been indentured servants at some time, actively indentured servants were outnumbered by non-indentured workers, or by those whose indenture had expired. Thus free wage labor was more common for Europeans in the colonies. Indentured persons were numerically important mostly in the region from Virginia north to New Jersey. Other colonies saw far fewer of them. The total number of European immigrants to all 13 colonies before 1775 was 500,000–550,000; of these, 55,000 were involuntary prisoners. Of the 450,000 or so European arrivals who came voluntarily, Tomlins estimates that 48% were indentured. About 75% were under the age of 25. The age of legal adulthood for men was 24 years; those over 24 generally came on contracts lasting about 3 years. Regarding the children who came, Gary Nash reports that, "many of the servants were actually nephews, nieces, cousins and children of friends of emigrating Englishmen, who paid their passage in return for their labor once in America."

Farmers, merchants, and shopkeepers in the British colonies found it very difficult to hire free workers, primarily because it was easy for potential workers to set up their own farms. Consequently, a common solution was to transport a young worker from Britain or a German state, who would work for several years to pay off the debt of their travel costs. During the indenture period the servants were not paid cash wages, but were provided with food, accommodation, clothing and training. The indenture document specified how many years the servant would be required to work, after which they would be free. Terms of indenture ranged from one to seven years with typical terms of four or five years. In southern New England, a variant form of indentured servitude, which controlled the labor of Native Americans through an exploitative debt-peonage system, developed in the late 17th century and continued through to the period of the American Revolution.

Not all European servants came willingly. Several instances of kidnapping for transportation to the Americas are recorded, though these were often indentured in the same way as their willing counterparts. An illustrative example is that of Peter Williamson (1730–1799). As historian Richard Hofstadter pointed out, "Although efforts were made to regulate or check their activities, and they diminished in importance in the eighteenth century, it remains true that a certain small part of the white colonial population of America was brought by force, and a much larger portion came in response to deceit and misrepresentation on the part of the spirits [recruiting agents]."

Many white immigrants arrived in colonial America as indentured servants, usually as young men and women from Britain or Germany, under the age of 21. Typically, the father of a teenager would sign the legal papers, and work out an arrangement with a ship captain, who would not charge the father any money. The captain would transport the indentured servants to the American colonies, and sell their legal papers to someone who needed workers. At the end of the indenture, the young person was given a new suit of clothes and was free to leave. Many immediately set out to begin their own farms, while others used their newly acquired skills to pursue a trade. A few became sufficiently prosperous that they were eventually able to acquire indentured servants of their own.

Given the high death rate, many servants did not live to the end of their terms. In the 18th and early 19th century, numerous Europeans, mostly from outside the British Isles, traveled to the colonies as redemptioners, a particularly harsh form of indenture.

Indentured servants were a separate category from bound apprentices. The latter were American-born children, usually orphans or from an impoverished family who could not care for them. They were under the control of courts and were bound out to work as an apprentice until a certain age. Two famous bound apprentices were Benjamin Franklin who illegally fled his apprenticeship to his brother, and Andrew Johnson, who later became President of the United States.

George Washington used indentured servants; in April 1775, he offered a reward for the return of two runaway white servants.

Development

Indentured servitude in the Americas was first used by the Virginia Company in the early seventeenth century as a method for collateralizing the debt finance for transporting people to its newfound British colonies.

Before the rise of indentured servitude, a large demand for labor existed in the colonies to help build settlements, farm crops and serve as tradesmen, but many laborers in Europe could not afford the transatlantic crossing, which could cost roughly half a worker's annual wage.

European financial institutions could not easily lend to the workers since there was no effective way to enforce a loan from across the Atlantic, rendering labor immobile via the Atlantic because of capital market imperfections.

To address this imperfection, the Virginia Company would allow laborers to borrow against their future earnings at the Virginia Company for a fixed number of years in order to raise sufficient capital to pay for their voyage. Evidence shows this practice was in use by 1609, only two years after the founding of the Virginia Company's original Jamestown settlement. However, this practice created a financial risk for the Virginia Company. If workers died or refused to work, the investment would be lost.

By 1620, the Virginia Company switched to selling contracts of "one hundred servants to be disposed among the old Planters" as soon as the servants reached the colonies. This minimized risk on its investment to the two–three months of transatlantic voyage. As the system gained in popularity, individual farmers and tradesmen would eventually begin investing in indentured servants as well.

The archaeological excavation of a 17th-century Maryland residence in Anne Arundel County discovered what was most likely an indentured servant who was murdered, buried and hidden beneath the floor alongside a garbage pit. In 1661 Virginia law prohibited the inappropriate burial of indentured servants. The Transportation Act 1717 established a regulated system for indentured criminal laborers.

In the 18th century, wages in Great Britain were low because of a surplus of labor. The average monetary wage was about 50 shillings (£2.50, equivalent to £474 in 2023) a year for a plowman, and 40 shillings (£2) a year for an ordinary unskilled worker. Ships' captains negotiated prices for transporting and feeding a passenger on the seven- or eight-week journey across the ocean, averaging about £5 to £7, equivalent to years of work back in England.

Still, demand for indentured labor remained relatively low until the adoption of staple crops, such as sugarcane in the West Indies or tobacco in the American South. With economies largely based on these crops, the West Indies and American South would see the vast majority of indentured labour.

An indenture signed by Henry Mayer, with an "X", in 1738. This contract bound Mayer to Abraham Hestant of Bucks County, Pennsylvania, who had paid for Mayer to travel from Europe.

Author and historian Richard Hofstadter has written:

The most unenviable situation was that of servants on Southern plantations, living alongside but never with Negro slaves, both groups doing much the same work, often under the supervision of a relentless overseer… Even as late as 1770, William Eddis, the English surveyor of customs at Annapolis, thought that the Maryland Negroes were better off than "the Europeans, over whom the rigid planter exercises an inflexible severity." The Negroes, Eddis thought, were a lifelong property so were treated with a certain care, but the whites were "strained to the utmost to perform their allotted labour."

Over time the market for indentured servitude developed, with length of contracts showing close correlations to indicators of health and productivity. Tall, strong, healthy, literate or skilled servants would often serve shorter terms than less productive or more sickly servants. Similarly, destinations with harsh working climates such as the West Indies would come to offer shorter contracts compared to the more hospitable colonies.

The majority of indentured servants ended up in the American South, where cash crops necessitated labor-intensive farming. As the Northern colonies moved toward industrialization, they received far less indentured immigration. For example, 96% of English emigrants to Virginia and Maryland from 1773 to 1776 were indentured servants. During the same time period, 2% of English emigrants to New England were indentured.

Indenture of apprenticeship binding Evan Morgan, a child aged 6 years and 11 months, for a period of 14 years, 1 month. Dated Feb. 1, 1823, Sussex Co., Delaware.

An indenture was a legal contract enforced by the courts. One indenture reads as follows:

This INDENTURE Witnesseth that James Best a Labourer doth Voluntarily put himself Servant to Captain Stephen Jones Master of the Snow Sally to serve the said Stephen Jones and his Assigns, for and during the full Space, Time and Term of three Years from the first Day of the said James’ arrival in Philadelphia in AMERICA, during which Time or Term the said Master or his Assigns shall and will find and supply the said James with sufficient Meat, Drink, Apparel, Lodging and all other necessaries befitting such a Servant, and at the end and expiration of said Term, the said James to be made Free, and receive according to the Custom of the Country. Provided nevertheless, and these Presents are on this Condition, that if the said James shall pay the said Stephen Jones or his Assigns 15 Pounds British in twenty one Days after his arrival he shall be Free, and the above Indenture and every Clause therein, absolutely Void and of no Effect. In Witness whereof the said Parties have hereunto interchangeably put their Hands and Seals the 6th Day of July in the Year of our Lord, One Thousand Seven Hundred and Seventy Three in the Presence of the Right Worshipful Mayor of the City of London. (signatures)

When the ship arrived, the captain would often advertise in a newspaper that indentured servants were for sale:

Just imported, on board the Snow Sally, Captain Stephen Jones, Master, from England, A number of healthy, stout English and Welsh Servants and Redemptioners, and a few Palatines [Germans], amongst whom are the following tradesmen, viz. Blacksmiths, watch-makers, coppersmiths, taylors, shoemakers, ship-carpenters and caulkers, weavers, cabinet-makers, ship-joiners, nailers, engravers, copperplate printers, plasterers, bricklayers, sawyers and painters. Also schoolmasters, clerks and book-keepers, farmers and labourers, and some lively smart boys, fit for various other employments, whose times are to be disposed of. Enquire of the Captain on board the vessel, off Walnut-street wharff, or of MEASE and CALDWELL.

When a buyer was found, the sale would be recorded at the city court. The Philadelphia Mayor’s Court Indenture Book, page 742, for September 18, 1773 has the following entry:

James Best, who was under Indenture of Redemption to Captain Stephen Jones now cancelled in consideration of £ 15, paid for his Passage from London bound a servant to David Rittenhouse of the City of Philadelphia & assigns three years to be found all necessaries.

Restrictions

Indentures could not marry without the permission of their owner, were subject to physical punishment (like many young ordinary servants), and saw their obligation to labor enforced by the courts. To ensure uninterrupted work by the female servants, the law lengthened the term of their indenture if they became pregnant. But unlike slaves, servants were guaranteed to be eventually released from bondage. At the end of their term they received a payment known as "freedom dues" and became free members of society. One could buy and sell indentured servants' contracts, and the right to their labor would change hands, but not the person as a piece of property.

Both male and female laborers could be subject to violence, occasionally even resulting in death. Richard Hofstadter notes that, as slaves arrived in greater numbers after 1700, white laborers in Virginia became a "privileged stratum, assigned to lighter work and more skilled tasks". He also notes that "Runaways were regularly advertised in the newspapers, rewards were offered, and both sheriffs and the general public were enlisted to secure their return. ... The standard penalty in the North, not always rigorously enforced, was extra service of twice the time the master had lost, though whipping was also common."

Redemptioner profile

Indentured servitude was a method of increasing the number of colonists, especially in the English and later British colonies. Voluntary migration and convict labor only provided so many people, and since the journey across the Atlantic was dangerous, other means of encouraging settlement were necessary. Contract-laborers became an important group of people and so numerous that the United States Constitution counted them specifically in appointing representatives:

Representatives and direct Taxes shall be apportioned among the several States which may be included within this Union, according to their respective Numbers, which shall be determined by adding to the whole Number of free Persons, including those bound to Service for a Term of Years....

Displaced from their land and unable to find work in the cities, many of these people signed contracts of indenture and took passage to the Americas. In Massachusetts, religious instruction in the Puritan way of life was often part of the condition of indenture, and people tended to live in towns.

The labor-intensive cash crop of tobacco was farmed in the American South by indentured laborers in the 17th and 18th centuries. Indentured servitude was not the same as the apprenticeship system by which skilled trades were taught, but similarities do exist between the two, since both require a set period of work. The majority of Virginians were Anglican, not Puritan, and while religion did play a large role in everyday lives, the culture was more commercially based. In the Chesapeake and North Carolina, tobacco constituted a major percentage of the total agricultural output. In the Deep South (mainly Georgia and South Carolina), cotton and rice plantations dominated. In the lower Atlantic colonies where tobacco was the main cash crop, the majority of labor that indentured servants performed was related to field work. In this situation, social isolation could increase the possibilities for both direct and indirect abuse, as could lengthy, demanding labor in the tobacco fields.

The system was still widely practiced in the 1780s, picking up immediately after a hiatus during the American Revolution. Fernand Braudel (The Perspective of the World 1984, pp. 405ff) instances a 1783 report on "the import trade from Ireland" and its large profits to a ship owner or a captain, who:

...puts his conditions to the emigrants in Dublin or some other Irish port. Those who can pay for their passage—usually about 100 or 80 [livres tournois]—arrive in America free to take any engagement that suits them. Those who cannot pay are carried at the expense of the shipowner, who in order to recoup his money, advertises on arrival that he has imported artisans, laborers and domestic servants and that he has agreed with them on his own account to hire their services for a period normally of three, four, or five years for men and women and 6 or 7 years for children.

In modern terms, the shipowner was acting as a contractor, hiring out his laborers. Such circumstances affected the treatment a captain gave his valuable human cargo. After indentures were forbidden, the passage had to be prepaid, giving rise to the inhumane conditions of Irish 'coffin ships' in the second half of the 19th century.

Southern New England Native Americans and indenture

Starting in the late 17th century, in southern New England and parts of Long Island, Native Americans were increasingly pulled into an exploitative debt-peonage system designed to control and assimilate Native American people into the dominant culture as well as channel their labor into the market-based Atlantic economy. Following King Philip's War (1675–1676) most Native Americans in the region were resigned to reservations or lived in increasingly marginal enclaves on the edges of colonial towns. Due to restricted access to resources, land loss, and changes to the environment caused by European settlement, many Native Americans, especially coastal groups, could no longer practice traditional subsistence activities and therefore became increasingly dependent on European trade goods—cloth, tools, guns, alcohol, and increasingly, food. Merchants trading these items to Native Americans often inflated the cost and, based on a predatory lending scheme, advanced them credit for these purchases, knowing full well most Native Americans would not be able to repay the debts. Eventually when debts mounted, Native Americans were hauled into court by their creditors. When they could not pay either their lands, or more commonly their labor, was seized to settle the debt. Native American debtors were then indentured to their creditors for terms ranging from a few months to sometimes years. Rare cases exist when Native Americans were indentured for a decade or more and a few were enslaved for life (this was quite rare however). Many Native Americans experienced repeated indentures over the course of their lifetimes, amounting to a phenomenon of 'serial indenture' or debt peonage—multiple short indentures alternating with brief periods of 'freedom.' The 'time' Native American servants owed could be sold or willed to heirs if a creditor died.

Assessing how many Native Americans experienced indenture is difficult as exact Native American populations during the colonial period are unknown. However, Historian John Sainsbury was able to document that by the mid-18th century about a third of all Native Americans in Rhode Island were indentured servants living and working in white households. Also, the Massachusetts state archives contains numerous petitions, written from the 1730s to 1760s from Native American tribes in their jurisdiction complaining about abuses in the indenture system and predatory lending by whites. Statutes were eventually passed attempting to regulate practices. Colonial military records do provide some data on Native American indenture as well. Enlistment records from 1704 to 1726 show that almost two-thirds of Native Americans who joined the army were indentured at the time of their enlistment. Records from 1748 to 1760 show a decline in this rate, but still show almost a third of Native American recruits being bound to white masters at the time of their enlistment. One Connecticut regiment raised in 1746 during King George's War (containing 980 men total) contained 139 Native American men. Almost half of them had signed their wages over to white creditors before being deployed.

While many Native American men, women and children became servants in New England households, the labor of many adult men was funneled into the whaling industry on Long Island, Rhode Island, Cape Cod and the islands of Martha's Vineyard and Nantucket, as well as the coast of eastern Connecticut. These whaling indentures were somewhat distinct from normal indenture contracts, and stipulated that Native Americans serve not as servants in white households but instead as crew members on a certain number of whaling voyages or 'seasons' of whaling (typically November through April). Throughout most of the colonial period indentured or heavily indebted Native American whalers were the primary labor force in the early whaling industry. They remained an important source of labor into the Revolutionary and early national era, but as their numbers dwindled and the industry expanded exponentially, they made up a decreasingly small proportion of the labor force.

Text of Whaling Indenture Contract of Isaac Pepenie (Wampanoag Indian) to James Lovell Jr. 1729.:

Witnesseth that Isaac Pepenie Indian of Falmouth, Barnstable labourer, hath ... of his own free will ... Bound and obliged himself to Serve James Lovell Junr ... a Sea faring man, on Diverse Whale Voiages in the several seasons ... the date of these presents: viz. this winter season in ... Barnstable, and the next Spring at Nantucket, and former season following in the sloops or vessels that ... [Lovell] desire[s], all which respective voyages ... and any and all materials for the performing of sd. Voyages ... he the said Isaac Pepenie to have one eighth and diet according to costom ... as shall be needful with his master for the sum of fifteen pounds which he the said James Lovell doth hereby agree to pay for him, ... then the sd. Pepenie doth by these [agreements] oblige himself to attend [the] Whale Voiages at the order and direction of said James Lovell, his administrators or assigns in manner aforesaid ... this first day of October in the Eleventh year of His Majesty's Reign ano dom 1729.

Isaac Papenie
Barnstable.

We the subscribers two of his Majestys Justices of the Peace for said County being present at the execution of the premesis do allow and approbate the same as just and reasonable.

Danl. Parker, Joseph Lothrop

Decline

Indentured servitude appeared in the Americas in the 1620s and remained in use as late as 1917. The causes behind its decline are a contentious domain in economic history.

The end of debtors' prisons may have created a limited commitment pitfall in which indentured servants could agree to contracts with ship captains and then refuse to sell themselves once they arrived in the colonies. Increased lobbying from immigrant aid societies led to increased regulation of the indentured labor market, further increasing the difficulty of enforcing contracts. With less ability to enforce the contracts, demand for indentured servants may have fallen. However, most debtor prisons were still in service when indentured servitude disappeared and many regulations on indentured servitude were put in place well before the practice's disappearance.

A rise in European per-capita income compared to passage fare during the nineteenth century may also explain the disappearance of indentured servitude. While passage from England to the colonies in 1668 would cost roughly 51 percent of English per-capita income, that ratio would decrease to between 20 and 30 percent by 1841. This increase in relative income may have been further supplemented by a demonstrated increase in savings among European laborers, meaning European emigrants would have the capital on hand to pay for their own passage. With no need for transit capital, fewer laborers would have become indentured, and the supply of indentured servants would have decreased.

Labor substitutions may have led employers away from indentured servants and towards slaves or paid employees. In many places, African slaves became cheaper for unskilled and then eventually skilled labor, and most farmhand positions previously filled by indentured servants were ultimately filled by slaves. Wage laborers may have been more productive, since employers were more willing to terminate waged employment. In comparison, firing an indentured servant would mean a loss on the original capital investment spent purchasing the servant's contract. Either substitution would lead to a decrease in demand for indentured servitude. An additional problem for employers was that, compared to African slaves, European indentured servants who ran away could not always be easily distinguished from the general white population, so they were more difficult to re-capture.

Indentured servitude's decline for white servants was also largely a result of changing attitudes that accrued over the 18th century and culminated in the early 19th century. Over the 18th century, the penal sanctions that were used against all workers were slowly going away from colonial codes, leaving indentured servants the only adult white labor subject to penal sanctions (with the notable exception of seaman, whose contracts could be criminally enforced up to the 20th century). These penal sanctions for indentured laborers continued in the United States until the 1830s, and by this point treatment of European laborers under contract became the same as the treatment of wage laborers (however, this change in treatment didn't apply to workers of color). This change in treatment can be attributed to a number of factors, such as the growing identification of white indented labor with slavery at a time when slavery was coming under attack in the Northern states, the growing radicalism of workers influenced with the rhetoric of the American Revolution, and the expansion of suffrage in many states which empowered workers politically. Penal sanctions, previously considered perfectly in line with free labor, became in the 19th century a way to transform ordinary labor into "contracts of slavery."

Labor market dynamics

Given the rapid expansion of colonial export industries in the 17th and 18th century, natural population growth and immigration were unable to meet the increasing demand for workers. As a result, the cost of indentured servants rose substantially. In the Chesapeake Bay, for example, the cost of indentures rose as much as 60% in the 1680s. The increase in the price of indentures did not motivate European workers to emigrate, for they did not benefit from the higher prices. As a result, the companies that generated indentures disrupted the price signaling effect, and thus the supply of immigrants did not expand sufficiently to meet demand. Some actors in the market attempted to generate incentives for workers by shortening the length of indenture contracts, based on the productivity of the prospective emigrant. Some American firms also opted to incentivize workers by paying small wages or by negotiating early expiration of indentures. These measures increased the cost of an indenture, while early termination made it less valuable.

The rising cost of indentured labor and its inelastic supply pushed American producers towards a cheaper alternative: enslaved workers. Not only were they substantially cheaper, the supply was more abundant; in contrast with indentured workers, they had to emigrate whether they wanted to or not. No incentives were necessary, although higher prices motivated slave traders to expand "production" (in the form of raiding expeditions). Supply was relatively elastic. Slavery thus was better able to satisfy labor demands in colonies requiring large quantities of unskilled agricultural workers (for example, plantation colonies in the Caribbean). Indentures, however, prevailed in colonies that required skilled workers, since the cost of an indenture was less than the cost of training an enslaved worker. Alison Smith and Abbott E. Smith's analysis of London port records shows how the destinations of indentured emigrants shifted from the West Indies towards New England as early as the 1660s, supporting the theory that indentured servitude might have declined in some regions because of labor market dynamics.

Affordability of immigration

The rise in the affordability of immigration reduced emigrants’ need for external financing in the form of indentures. David Galenson's analysis on affordability shows that the cost of immigration from Britain to the United States over the course of the 18th century dropped from 50% of per capita income to less than 10%. This is attributable to higher levels of real income in Europe (a result of economic growth in the 18th century) and to a sharp decline in transportation costs. Innovation had a strong impact on the ease and cost of passenger transportation, reducing the need of indentures. The railroad made non-port cities a much cheaper destination for immigrants. The steamboat was not necessarily cheaper than older sailing technologies, but it made transatlantic travel much easier and comfortable, an attractive factor for high-income classes (that could easily afford immigration without indentures).[67]

The British Navy's efforts against piracy also reduced transportation costs. Safer seas implied smaller crews (for there was no need to man weapons on board) and also reduced insurance costs (ships were at lower risk of being captured).

The composition of immigrants also shifted from single males towards entire families. Single males usually left their homes with little if any savings. Instead, families generally liquidated assets in Europe to finance their venture.

Impact of American Revolution

The American Revolution severely limited immigration to the United States. Economic historians differ however on the long-term impact of the Revolution. Sharon Salinger argues that the economic crisis that followed the war made long-term labor contracts unattractive. Her analysis of Philadelphia's population shows how the percentage of bound citizens fell from 17% to 6% over the course of the war. William Miller posits a more moderate theory, stating "the Revolution (…) wrought disturbances upon white servitude. But these were temporary rather than lasting". David Galenson supports this theory by proposing that British indentures never recovered, but Europeans from other nationalities replaced them.

In 1799 New York State passed the Act for the Gradual Abolition of Slavery. Existing slaves became indentured servants. That status was finally ended in 1827 and all the indentured obtained full freedom.

A number of acts passed by both the American and the British governments fostered the decline of indentures. The British Passenger Vessels Act 1803, which regulated travel conditions aboard ships, attempted to make transportation more expensive in order to stop emigration. The American abolition of imprisonment of debtors by federal law (passed in 1833) made prosecution of runaway servants more difficult, increasing the risk of indenture contract purchases.

In the 19th century, most indentures of this nature occurred in the old Northwest Territory. The permissibility of such indentures centered on the interpretation of "involuntary servitude" per the 1787 Northwest Ordinance, which declared:

There shall be neither slavery nor involuntary servitude in the territory otherwise than in the punishment of crimes, whereof the Party shall have been duly convicted.

The permissibility (or not) of penal sanctions in labor became an issue of "fundamental law", in which it was questioned whether those sanctions or specific performance enforcements turned indentured servitude into "involuntary servitude". At the time when the Northwest Ordinance was constructed, white adult servants were still being imported into the United States, and thus, historically, it seems likely that the Ordinance's framers considered indenture to be a form of "voluntary" servitude. In essence, this means the indentured servant chose to work for someone who bought them something.

The Territory of Hawaii was the last place in the United States to widely use indentures, as by 1900 the practice had been abolished in the rest of the country and replaced by alternatives such as the credit-ticket system used to transport Chinese laborers. Prior to U.S. annexation, indentures were widely used to transport Japanese contract workers to Hawaii for plantation work. In the Hawaiian Organic Act of 1900 the U.S. prohibited further use of indentures in the territory and voided all such existing contracts, thus ending the practice.

Caribbean

European servants in colonies

A half million Europeans went as indentured servants to the Caribbean (primarily the English-speaking islands of the Caribbean) before 1840. Most were young men, with dreams of owning their own land or striking it rich quick, who would essentially sell years of their labor in exchange for passage to the islands. However, forceful indenture also provided part of the servants: contemporaries report that youngsters were sometimes tricked into servitude in order to be exploited in the colonies.

The landowners on the islands would pay for a servant's passage and then provide the servant with food, clothes, shelter and instruction during the agreed term. The servant would then be required to work in the landowner's field for a term of bondage (usually four to seven years). Servants were not allowed to marry without the master's permission. Servants could own personal property. They could also complain to a local magistrate about mistreatment that exceeded community norms. However, a servant's contract could be sold or given away by his master.

After the servant's term was complete he became independent and was paid "freedom dues". These payments could take the form of land which would give the servant the opportunity to become an independent farmer or a free laborer. As free men with little money they became a political force that stood in opposition to the rich planters.

Indentured servitude was a common part of the social landscape in England and Ireland during the 17th century. During the 17th century, British and Irish went to Barbados as both masters and as indentured servants. Some went as prisoners. During the Wars of the Three Kingdoms many Scottish and Irish prisoners of war were sold as indentured laborers to the colonies. There were also reports of kidnappings of youngsters to work as servants.

After 1660, fewer indentured servants came from Europe to the Caribbean. Newly freed servant farmers, given 25–50 acres of land, were unable to make a living because profitable sugar plantations needed to cover hundreds of acres. However, profit could still be made through the tobacco trade, which was what these small 25-acre farms did to live comfortably. The landowners’ reputation as cruel masters became a deterrent to the potential indentured servant. In the 17th century, the islands became known as death traps, as between 33 and 50 percent of indentured servants died before they were freed, many from yellow fever, malaria and other diseases.

Indian servants after abolition

When slavery ended in the British Empire in 1833, plantation owners turned to indentured servitude for inexpensive labor. These servants arrived from across the globe; the majority came from India where many indentured laborers came from to work in colonies requiring manual labor. As a result, today Indo-Caribbean people make up a plurality in Guyana, Trinidad and Tobago and Suriname, and a substantial minority in Jamaica, Grenada, Barbados, St Lucia and other Caribbean islands. The British government finally ended indentures in the Caribbean in 1917 by prohibiting the further transportation of persons from India for purposes of servitude for debt.

Dialectical behavior therapy

From Wikipedia, the free encyclopedia
The skills modules in dialectical behavior therapy

Dialectical behavior therapy (DBT) is an evidence-based psychotherapy that began with efforts to treat personality disorders and interpersonal conflicts. Evidence suggests that DBT can be useful in treating mood disorders and suicidal ideation as well as for changing behavioral patterns such as self-harm and substance use. DBT evolved into a process in which the therapist and client work with acceptance and change-oriented strategies and ultimately balance and synthesize them—comparable to the philosophical dialectical process of thesis and antithesis, followed by synthesis.

This approach was developed by Marsha M. Linehan, a psychology researcher at the University of Washington. She defines it as "a synthesis or integration of opposites". DBT was designed to help people increase their emotional and cognitive regulation by learning about the triggers that lead to reactive states and by helping to assess which coping skills to apply in the sequence of events, thoughts, feelings, and behaviors to help avoid undesired reactions. Linehan later disclosed to the public her own struggles and belief that she suffers from borderline personality disorder.

DBT grew out of a series of failed attempts to apply the standard cognitive behavioral therapy (CBT) protocols of the late 1970s to chronically suicidal clients. Research on its effectiveness in treating other conditions has been fruitful. DBT has been used by practitioners to treat people with depression, drug and alcohol problems, post-traumatic stress disorder (PTSD), traumatic brain injuries (TBI), binge-eating disorder, and mood disorders. Research indicates that DBT might help patients with symptoms and behaviors associated with spectrum mood disorders, including self-injury. Work also suggests its effectiveness with sexual-abuse survivors and chemical dependency.

DBT combines standard cognitive-behavioral techniques for emotion regulation and reality-testing with concepts of distress tolerance, acceptance, and mindful awareness largely derived from contemplative meditative practice. DBT is based upon the biosocial theory of mental illness and is the first therapy that has been experimentally demonstrated to be generally effective in treating borderline personality disorder (BPD). The first randomized clinical trial of DBT showed reduced rates of suicidal gestures, psychiatric hospitalizations, and treatment dropouts when compared to usual treatment. A meta-analysis found that DBT reached moderate effects in individuals with BPD. DBT may not be appropriate as a universal intervention, as it was shown to be harmful or have null effects in a study of an adapted DBT skills-training intervention in adolescents in schools, though conclusions of iatrogenic harm are unwarranted as the majority of participants did not significantly engage with the assigned activities with higher engagement predicting more positive outcomes.

Overview

DBT is sometimes considered a part of the "third wave" of cognitive-behavioral therapy, as DBT adapts CBT to assist patients in dealing with stress. DBT focuses on treating disorders that are characterised by impulsivity and emotional dysregulation.

DBT strives to have the patient view the therapist as an accepting ally rather than an adversary in the treatment of psychological issues: many treatments at this time left patients feeling "criticized, misunderstood, and invalidated" due to the way these methods "focused on changing cognitions and behaviors." Accordingly, the therapist aims to accept and validate the client's feelings at any given time, while, nonetheless, informing the client that some feelings and behaviors are maladaptive, and showing them better alternatives. In particular, DBT targets self-harm and suicide attempts by identifying the function of that behavior and obtaining that function safely through DBT coping skills. DBT focuses on the client acquiring new skills and changing their behaviors, with the ultimate goal of achieving a "life worth living".

In DBT's biosocial theory of BPD, clients have a biological predisposition for emotional dysregulation, and their social environment validates maladaptive behavior.

DBT skills training alone is being used to address treatment goals in some clinical settings, and the broader goal of emotion regulation that is seen in DBT has allowed it to be used in new settings, for example, supporting parenting. There has been little study into adapting DBT into an online environment, but a review indicates that attendance is improved online, with comparable improvements for clients to the traditional mode.

Four modules

Mindfulness

DBT wise mind—the synthesis of the two opposites: reasonable mind and emotion mind

Mindfulness is one of the core ideas behind all elements of DBT. It is considered a foundation for the other skills taught in DBT, because it helps individuals accept and tolerate the powerful emotions they may feel when challenging their habits or exposing themselves to upsetting situations.

The concept of mindfulness and the meditative exercises used to teach it are derived from traditional contemplative religious practice, though the version taught in DBT does not involve any religious or metaphysical concepts. Within DBT it is the capacity to pay attention, nonjudgmentally, to the present moment; about living in the moment, experiencing one's emotions and senses fully, yet with perspective. The practice of mindfulness can also be intended to make people more aware of their environments through their five senses: touch, smell, sight, taste, and sound. Mindfulness relies heavily on the principle of acceptance, sometimes referred to as "radical acceptance". Acceptance skills rely on the patient's ability to view situations with no judgment, and to accept situations and their accompanying emotions. This causes less distress overall, which can result in reduced discomfort and symptomology.

Acceptance and change

The first few sessions of DBT introduce the dialectic of acceptance and change. The patient must first become comfortable with the idea of therapy; once the patient and therapist have established a trusting relationship, DBT techniques can flourish. An essential part of learning acceptance is to first grasp the idea of radical acceptance: radical acceptance embraces the idea of facing situations, both positive and negative, without judgment. Acceptance also incorporates mindfulness and emotional regulation skills, which depend on the idea of radical acceptance. These skills, specifically, are what set DBT apart from other therapies.

Often, after a patient becomes familiar with the idea of acceptance, they will accompany it with change. DBT has five specific states of change which the therapist will review with the patient: pre-contemplation, contemplation, preparation, action, and maintenance. Precontemplation is the first stage, in which the patient is completely unaware of their problem. In the second stage, contemplation, the patient realizes the reality of their illness: this is not an action, but a realization. It is not until the third stage, preparation, that the patient is likely to take action, and prepares to move forward. This could be as simple as researching or contacting therapists. Finally, in stage 4, the patient takes action and receives treatment. In the final stage, maintenance, the patient must strengthen their change in order to prevent relapse. After grasping acceptance and change, a patient can fully advance to mindfulness techniques.

There are six mindfulness skills used in DBT to bring the client closer to achieving a "wise mind", the synthesis of the rational mind and emotional mind: three "what" skills (observe, describe, participate) and three "how" skills (nonjudgementally, one-mindfully, effectively).

Distress tolerance

The concept of distress tolerance arose from methods used in person-centered, psychodynamic, psychoanalytic, gestalt, and/or narrative therapies, along with religious and spiritual practices. Distress tolerance means learning to bear emotional discomfort skillfully, without resorting to maladaptive reactions. Healthier coping behaviors are learned, including intentional self-distraction, self-soothing, and 'radical acceptance.'

Distress tolerance skills are meant to arise naturally as a consequence of mindfulness. They have to do with the ability to accept, in a non-evaluative and nonjudgmental fashion, both oneself and the current situation. It is meant to be a non-judgmental stance, one of neither approval nor resignation. The goal is to become capable of calmly recognizing negative situations and their impact, rather than becoming overwhelmed or hiding from them. This allows individuals to make wise decisions about whether and how to take action, rather than falling into intense, desperate, and often destructive emotional reactions.

Emotion regulation

Individuals with borderline personality disorder and suicidal individuals are frequently emotionally intense and labile. They can be angry, intensely frustrated, depressed, or anxious. The theory holds that intense emotions are conditioned responses to distressing experiences, which serve as the conditioned stimuli. Emotional regulation skills are taught to help patients modify their conditioned responses.

Dialectical behavior therapy skills for emotion regulation include:

  • Learning how to understand and name emotions: the patient focuses on recognizing their feelings. This segment relates directly to mindfulness, which also exposes a patient to their emotions.
  • Identify obstacles to changing emotions
  • Changing unwanted emotions: the therapist emphasizes the use of opposite-reactions, fact-checking, and problem solving to regulate emotions. While using opposite-reactions, the patient targets distressing feelings by responding with the opposite emotion.
  • Reducing vulnerability: the patient learns to accumulate positive emotions and to plan coping mechanisms in advance, in order to better handle difficult experiences in the future.
  • Increase mindfulness to current emotions
  • Take opposite action
  • Apply distress tolerance techniques
  • Managing extreme conditions: the patient focuses on incorporating their use of mindfulness skills to their current emotions, to remain stable and alert in a crisis.

Interpersonal effectiveness

The three interpersonal skills focused on in DBT include self-respect, treating others "with care, interest, validation, and respect", and assertiveness. The dialectic involved in healthy relationships involves balancing the needs of others with the needs of the self, while maintaining one's self-respect.

Tools

Diary cards

Specially formatted diary cards can be used to track relevant emotions and behaviors. Diary cards are most useful when they are filled out daily. The diary card is used to find the treatment priorities that guide the agenda of each therapy session. Both the client and therapist can use the diary card to see what has improved, gotten worse, or stayed the same.

Chain analysis

Chain analysis— from a prompting event to the problem behavior and consequences

Chain analysis is a form of functional analysis of behavior but with increased focus on sequential events that form the behavior chain. It has strong roots in behavioral psychology in particular applied behavior analysis concept of chaining. A growing body of research supports the use of behavior chain analysis with multiple populations.

Efficacy

Borderline personality disorder

DBT is the therapy that has been studied the most for treatment of borderline personality disorder, and there have been enough studies done to conclude that DBT is helpful in treating borderline personality disorder. Several studies have found there are neurobiological changes in individuals with BPD after DBT treatment.

Depression

A Duke University pilot study compared treatment of depression by antidepressant medication to treatment by antidepressants and dialectical behavior therapy. A total of 34 chronically depressed individuals over age 60 were treated for 28 weeks. Six months after treatment, statistically significant differences were noted in remission rates between groups, with a greater percentage of patients treated with antidepressants and dialectical behavior therapy in remission.

Complex post-traumatic stress disorder (CPTSD)

Exposure to complex trauma, or the experience of prolonged trauma with little chance of escape, can lead to the development of complex post-traumatic stress disorder (CPTSD) in an individual. The American Psychiatric Association (APA) does not recognize CPTSD as a diagnosis in the DSM-5 (Diagnostical and Statistical Manual of Mental Disorders, the manual used by providers to diagnose, treat and discuss mental illness), though many practitioners argue that CPTSD is separate from post-traumatic stress disorder (PTSD). As of 2020, over 40 studies from 15 different countries had "consistently demonstrated the distinction between PTSD and CPTSD" and "replicated the distinct symptoms associated with each disorder" according to a 2021 literature review.

CPTSD is similar to PTSD in that its symptomatology is pervasive and includes cognitive, emotional, and biological domains, among others. CPTSD differs from PTSD in that it is believed to originate in childhood interpersonal trauma, or chronic childhood stress, and that the most common precedents are sexual traumas. Currently, the prevalence rate for CPTSD is an estimated 0.5%, while PTSD's is 1.5%. Numerous definitions for CPTSD exist. Different versions are contributed by the World Health Organization (WHO), The International Society for Traumatic Stress Studies (ISTSS), and individual clinicians and researchers.

Most definitions revolve around criteria for PTSD with the addition of several other domains. While The APA may not recognize CPTSD, the WHO has recognized this syndrome in its 11th edition of the International Classification of Diseases (ICD-11). The WHO defines CPTSD as a disorder following a single or multiple events which cause the individual to feel stressed or trapped, characterized by low self-esteem, interpersonal deficits, and deficits in affect regulation. These deficits in affect regulation, among other symptoms are a reason why CPTSD is sometimes compared with borderline personality disorder (BPD).

Similarities Between CPTSD and borderline personality disorder

In addition to affect dysregulation, case studies reveal that patients with CPTSD can also exhibit splitting, mood swings, and fears of abandonment. Like patients with borderline personality disorder, patients with CPTSD were traumatized frequently and/or early in their development and never learned proper coping mechanisms. These individuals may use avoidance, substances, dissociation, and other maladaptive behaviors to cope. Thus, treatment for CPTSD involves stabilizing and teaching successful coping behaviors, affect regulation, and creating and maintaining interpersonal connections. In addition to sharing symptom presentations, CPTSD and BPD can share neurophysiological similarities, for example, abnormal volume of the amygdala (emotional memory), hippocampus (memory), anterior cingulate cortex (emotion), and orbital prefrontal cortex (personality). Another shared characteristic between CPTSD and BPD is the possibility for dissociation. Further research is needed to determine the reliability of dissociation as a hallmark of CPTSD, however it is a possible symptom. Because of the two disorders' shared symptomatology and physiological correlates, psychologists began hypothesizing that a treatment which was effective for one disorder may be effective for the other as well.

DBT as a treatment for CPTSD

DBT's use of acceptance and goal orientation as an approach to behavior change can help to instill empowerment and engage individuals in the therapeutic process. The focus on the future and change can help to prevent the individual from becoming overwhelmed by their history of trauma. This is a risk especially with CPTSD, as multiple traumas are common within this diagnosis. Generally, care providers address a client's suicidality before moving on to other aspects of treatment. Because PTSD can make an individual more likely to experience suicidal ideation, DBT can be an option to stabilize suicidality and aid in other treatment modalities.

Some critics argue that while DBT can be used to treat CPTSD, it is not significantly more effective than standard PTSD treatments. Further, this argument posits that DBT decreases self-injurious behaviors (such as cutting or burning) and increases interpersonal functioning but neglects core CPTSD symptoms such as impulsivity, cognitive schemas (repetitive, negative thoughts), and emotions such as guilt and shame. The ISTSS reports that CPTSD requires treatment which differs from typical PTSD treatment, using a multiphase model of recovery, rather than focusing on traumatic memories. The recommended multiphase model consists of establishing safety, distress tolerance, and social relations.

Because DBT has four modules which generally align with these guidelines (Mindfulness, Distress Tolerance, Affect Regulation, Interpersonal Skills) it is a treatment option. Other critiques of DBT discuss the time required for the therapy to be effective. Individuals seeking DBT may not be able to commit to the individual and group sessions required, or their insurance may not cover every session.

A study co-authored by Linehan found that among women receiving outpatient care for BPD and who had attempted suicide in the previous year, 56% additionally met criteria for PTSD. Because of the correlation between borderline personality disorder traits and trauma, some settings began using DBT as a treatment for traumatic symptoms. Some providers opt to combine DBT with other PTSD interventions, such as prolonged exposure therapy (PE) (repeated, detailed description of the trauma in a psychotherapy session) or cognitive processing therapy (CPT) (psychotherapy which addresses cognitive schemas related to traumatic memories).

For example, a regimen which combined PE and DBT would include teaching mindfulness skills and distress tolerance skills, then implementing PE. The individual with the disorder would then be taught acceptance of a trauma's occurrence and how it may continue to affect them throughout their lives. Participants in clinical trials of this DBT PE regimen exhibited a decrease in symptoms, and throughout the 12-week trial, no self-injurious or suicidal behaviors were reported. Later trials similarly show increased effectiveness versus DBT.

Another argument which supports the use of DBT as a treatment for trauma hinges upon PTSD symptoms such as emotion regulation and distress. Some PTSD treatments such as exposure therapy may not be suitable for individuals whose distress tolerance and/or emotion regulation is low. Biosocial theory posits that emotion dysregulation is caused by an individual's heightened emotional sensitivity combined with environmental factors (such as invalidation of emotions, continued abuse/trauma), and tendency to ruminate (repeatedly think about a negative event and how the outcome could have been changed).

An individual who has these features is likely to use maladaptive coping behaviors. DBT can be appropriate in these cases because it teaches appropriate coping skills and allows the individuals to develop some degree of self-sufficiency. The first three modules of DBT increase distress tolerance and emotion regulation skills in the individual, paving the way for work on symptoms such as intrusions, self-esteem deficiency, and interpersonal relations.

Noteworthy is that DBT has often been modified based on the population being treated. For example, in veteran populations DBT is modified to include exposure exercises and accommodate the presence of traumatic brain injury (TBI), and insurance coverage (i.e. shortening treatment). Populations with comorbid BPD may need to spend longer in the "Establishing Safety" phase. In adolescent populations, the skills training aspect of DBT has elicited significant improvement in emotion regulation and ability to express emotion appropriately. In populations with comorbid substance use, adaptations may be made on a case-by-case basis.

For example, a provider may wish to incorporate elements of motivational interviewing (psychotherapy which uses empowerment to inspire behavior change). The degree of substance use should also be considered. For some individuals, substance use is the only coping behavior they know, and as such the provider may seek to implement skills training before targeting substance reduction. Inversely, a client's substance use may be interfering with attendance or other treatment compliance and the provider may choose to address the substance use before implementing DBT for the trauma.

Computational science

From Wikipedia, the free encyclopedia

Computational science, also known as scientific computing, technical computing or scientific computation (SC), is a division of science, and more specifically the Computer Sciences, which uses advanced computing capabilities to understand and solve complex physical problems. While this typically extends into computational specializations, this field of study includes:

In practical use, it is typically the application of computer simulation and other forms of computation from numerical analysis and theoretical computer science to solve problems in various scientific disciplines. The field is different from theory and laboratory experiments, which are the traditional forms of science and engineering. The scientific computing approach is to gain understanding through the analysis of mathematical models implemented on computers. Scientists and engineers develop computer programs and application software that model systems being studied and run these programs with various sets of input parameters. The essence of computational science is the application of numerical algorithms and computational mathematics. In some cases, these models require massive amounts of calculations (usually floating-point) and are often executed on supercomputers or distributed computing platforms.

The computational scientist

Ways to study a system

The term computational scientist is used to describe someone skilled in scientific computing. Such a person is usually a scientist, an engineer, or an applied mathematician who applies high-performance computing in different ways to advance the state-of-the-art in their respective applied disciplines in physics, chemistry, or engineering.

Computational science is now commonly considered a third mode of science, complementing and adding to experimentation/observation and theory (see image). Here, one defines a system as a potential source of data, an experiment as a process of extracting data from a system by exerting it through its inputs and a model (M) for a system (S) and an experiment (E) as anything to which E can be applied in order to answer questions about S. A computational scientist should be capable of:

  • recognizing complex problems
  • adequately conceptualizing the system containing these problems
  • designing a framework of algorithms suitable for studying this system: the simulation
  • choosing a suitable computing infrastructure (parallel computing/grid computing/supercomputers)
  • hereby, maximizing the computational power of the simulation
  • assessing to what level the output of the simulation resembles the systems: the model is validated
  • adjusting the conceptualization of the system accordingly
  • repeat the cycle until a suitable level of validation is obtained: the computational scientist trusts that the simulation generates adequately realistic results for the system under the studied conditions

Substantial effort in computational sciences has been devoted to developing algorithms, efficient implementation in programming languages, and validating computational results. A collection of problems and solutions in computational science can be found in Steeb, Hardy, Hardy, and Stoop (2004).

Philosophers of science addressed the question to what degree computational science qualifies as science, among them Humphreys and Gelfert. They address the general question of epistemology: how does gain insight from such computational science approaches? Tolk uses these insights to show the epistemological constraints of computer-based simulation research. As computational science uses mathematical models representing the underlying theory in executable form, in essence, they apply modeling (theory building) and simulation (implementation and execution). While simulation and computational science are our most sophisticated way to express our knowledge and understanding, they also come with all constraints and limits already known for computational solutions.

Applications of computational science

Problem domains for computational science/scientific computing include:

Predictive computational science

Predictive computational science is a scientific discipline concerned with the formulation, calibration, numerical solution, and validation of mathematical models designed to predict specific aspects of physical events, given initial and boundary conditions, and a set of characterizing parameters and associated uncertainties. In typical cases, the predictive statement is formulated in terms of probabilities. For example, given a mechanical component and a periodic loading condition, "the probability is (say) 90% that the number of cycles at failure (Nf) will be in the interval N1<Nf<N2".

Urban complex systems

Cities are massively complex systems created by humans, made up of humans, and governed by humans. Trying to predict, understand and somehow shape the development of cities in the future requires complex thinking and computational models and simulations to help mitigate challenges and possible disasters. The focus of research in urban complex systems is, through modeling and simulation, to build a greater understanding of city dynamics and help prepare for the coming urbanization.

Computational finance

In financial markets, huge volumes of interdependent assets are traded by a large number of interacting market participants in different locations and time zones. Their behavior is of unprecedented complexity and the characterization and measurement of the risk inherent to this highly diverse set of instruments is typically based on complicated mathematical and computational models. Solving these models exactly in closed form, even at a single instrument level, is typically not possible, and therefore we have to look for efficient numerical algorithms. This has become even more urgent and complex recently, as the credit crisis has clearly demonstrated the role of cascading effects going from single instruments through portfolios of single institutions to even the interconnected trading network. Understanding this requires a multi-scale and holistic approach where interdependent risk factors such as market, credit, and liquidity risk are modeled simultaneously and at different interconnected scales.

Computational biology

Exciting new developments in biotechnology are now revolutionizing biology and biomedical research. Examples of these techniques are high-throughput sequencing, high-throughput quantitative PCR, intra-cellular imaging, in-situ hybridization of gene expression, three-dimensional imaging techniques like Light Sheet Fluorescence Microscopy, and Optical Projection (micro)-Computer Tomography. Given the massive amounts of complicated data that is generated by these techniques, their meaningful interpretation, and even their storage, form major challenges calling for new approaches. Going beyond current bioinformatics approaches, computational biology needs to develop new methods to discover meaningful patterns in these large data sets. Model-based reconstruction of gene networks can be used to organize the gene expression data in a systematic way and to guide future data collection. A major challenge here is to understand how gene regulation is controlling fundamental biological processes like biomineralization and embryogenesis. The sub-processes like gene regulation, organic molecules interacting with the mineral deposition process, cellular processes, physiology, and other processes at the tissue and environmental levels are linked. Rather than being directed by a central control mechanism, biomineralization and embryogenesis can be viewed as an emergent behavior resulting from a complex system in which several sub-processes on very different temporal and spatial scales (ranging from nanometer and nanoseconds to meters and years) are connected into a multi-scale system. One of the few available options to understand such systems is by developing a multi-scale model of the system.

Complex systems theory

Using information theory, non-equilibrium dynamics, and explicit simulations, computational systems theory tries to uncover the true nature of complex adaptive systems.

Computational science and engineering

Computational science and engineering (CSE) is a relatively new discipline that deals with the development and application of computational models and simulations, often coupled with high-performance computing, to solve complex physical problems arising in engineering analysis and design (computational engineering) as well as natural phenomena (computational science). CSE has become accepted amongst scientists, engineers and academics as the "third mode of discovery" (next to theory and experimentation). In many fields, computer simulation is integral and therefore essential to business and research. Computer simulation provides the capability to enter fields that are either inaccessible to traditional experimentation or where carrying out traditional empirical inquiries is prohibitively expensive. CSE should neither be confused with pure computer science, nor with computer engineering, although a wide domain in the former is used in CSE (e.g., certain algorithms, data structures, parallel programming, high-performance computing), and some problems in the latter can be modeled and solved with CSE methods (as an application area).

Methods and algorithms

Algorithms and mathematical methods used in computational science are varied. Commonly applied methods include:

Historically and today, Fortran remains popular for most applications of scientific computing.Other programming languages and computer algebra systems commonly used for the more mathematical aspects of scientific computing applications include GNU Octave, HaskellJuliaMapleMathematica, MATLABPython (with third-party SciPy library), Perl (with third-party PDL library), RScilab, and TK Solver. The more computationally intensive aspects of scientific computing will often use some variation of C or Fortran and optimized algebra libraries such as BLAS or LAPACK. In addition, parallel computing is heavily used in scientific computing to find solutions of large problems in a reasonable amount of time. In this framework, the problem is either divided over many cores on a single CPU node (such as with OpenMP), divided over many CPU nodes networked together (such as with MPI), or is run on one or more GPUs (typically using either CUDA or OpenCL).

Computational science application programs often model real-world changing conditions, such as weather, airflow around a plane, automobile body distortions in a crash, the motion of stars in a galaxy, an explosive device, etc. Such programs might create a 'logical mesh' in computer memory where each item corresponds to an area in space and contains information about that space relevant to the model. For example, in weather models, each item might be a square kilometer; with land elevation, current wind direction, humidity, temperature, pressure, etc. The program would calculate the likely next state based on the current state, in simulated time steps, solving differential equations that describe how the system operates, and then repeat the process to calculate the next state.

Conferences and journals

In 2001, the International Conference on Computational Science (ICCS) was first organized. Since then, it has been organized yearly. ICCS is an A-rank conference in the CORE ranking.

The Journal of Computational Science published its first issue in May 2010. The Journal of Open Research Software was launched in 2012. The ReScience C initiative, which is dedicated to replicating computational results, was started on GitHub in 2015.

Education

At some institutions, a specialization in scientific computation can be earned as a "minor" within another program (which may be at varying levels). However, there are increasingly many bachelor's, master's, and doctoral programs in computational science. The joint degree program master program computational science at the University of Amsterdam and the Vrije Universiteit in computational science was first offered in 2004. In this program, students:

  • learn to build computational models from real-life observations;
  • develop skills in turning these models into computational structures and in performing large-scale simulations;
  • learn theories that will give a firm basis for the analysis of complex systems;
  • learn to analyze the results of simulations in a virtual laboratory using advanced numerical algorithms.

ETH Zurich offers a bachelor's and master's degree in Computational Science and Engineering. The degree equips students with the ability to understand scientific problem and apply numerical methods to solve such problems. The directions of specializations include Physics, Chemistry, Biology and other Scientific and Engineering disciplines.

George Mason University has offered a multidisciplinary doctorate Ph.D. program in Computational Sciences and Informatics starting from 1992.

The School of Computational and Integrative Sciences, Jawaharlal Nehru University (erstwhile School of Information Technology) also offers a vibrant master's science program for computational science with two specialties: Computational Biology and Complex Systems.

Subfields

Computational thinking

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Computational_thinking

Computational thinking (CT) refers to the thought processes involved in formulating problems so their solutions can be represented as computational steps and algorithms. In education, CT is a set of problem-solving methods that involve expressing problems and their solutions in ways that a computer could also execute. It involves automation of processes, but also using computing to explore, analyze, and understand processes (natural and artificial).

History

The history of computational thinking as a concept dates back at least to the 1950s but most ideas are much older. Computational thinking involves ideas like abstraction, data representation, and logically organizing data, which are also prevalent in other kinds of thinking, such as scientific thinking, engineering thinking, systems thinking, design thinking, model-based thinking, and the like. Neither the idea nor the term are recent: Preceded by terms like algorithmizing, procedural thinking, algorithmic thinking, and computational literacy by computing pioneers like Alan Perlis and Donald Knuth, the term computational thinking was first used by Seymour Papert in 1980 and again in 1996. Computational thinking can be used to algorithmically solve complicated problems of scale, and is often used to realize large improvements in efficiency.

The phrase computational thinking was brought to the forefront of the computer science education community in 2006 as a result of a Communications of the ACM essay on the subject by Jeannette Wing. The essay suggests that thinking computationally is a fundamental skill for everyone, not just computer scientists, and argues for the importance of integrating computational ideas into other subjects in school. The essay also states that by learning computational thinking, children will be better in many everyday tasks; as examples, the essay gives packing one's backpack, finding one's lost mittens, and knowing when to stop renting and buying instead. The continuum of computational thinking questions in education ranges from K–9 computing for children to professional and continuing education, where the challenge is how to communicate deep principles, maxims, and ways of thinking between experts.

For the first ten years computational thinking was a US-centered movement, and still today that early focus is seen in the field's research. The field's most cited articles and most cited people were active in the early US CT wave, and the field's most active researcher networks are US-based. Dominated by US and European researchers, it is unclear to what extent can the field's predominantly Western body of research literature cater to the needs of students in other cultural groups. An ongoing effort to globalize effective thinking skills in everyday life is emerging in the Prolog community, whose Prolog Education Committee, sponsored by the Association for Logic Programming has the mission of "making Computational and Logical Thinking through Prolog and its successors a core subject in educational curricula and beyond, worldwide".

Characteristics

The characteristics that define computational thinking are decomposition, pattern recognition / data representation, generalization/abstraction, and algorithms. By decomposing a problem, identifying the variables involved using data representation, and creating algorithms, a generic solution results. The generic solution is a generalization or abstraction that can be used to solve a multitude of variations of the initial problem.

The "three As" Computational Thinking Process describes computational thinking as a set of three steps: abstraction, automation, and analysis.

Another characterization of computational thinking is the "three As" iterative process based on three stages:

  1. Abstraction: Problem formulation;
  2. Automation: Solution expression;
  3. Analysis: Solution execution and evaluation.

Connection to the "four Cs"

The four Cs of 21st-century learning are communication, critical thinking, collaboration, and creativity[citation needed]. The fifth C could be computational thinking which entails the capability to resolve problems algorithmically and logically. It includes tools that produce models and visualize data. Grover describes how computational thinking is applicable across subjects beyond science, technology, engineering, and mathematics (STEM) which include the social sciences and language arts.

Since its inception, the 4 Cs have gradually gained acceptance as important elements of many school syllabi. This development triggered modifications in platforms and directions such as inquiry, project-based, and more profound learning across all K–12 levels. Many countries have introduced computational thinking to all students: The United Kingdom has had CT in its national curriculum since 2012. Singapore calls CT "national capability". Other nations like Australia, China, Korea, and New Zealand have embarked on massive efforts to introduce computational thinking in schools. In the United States, President Barack Obama created the "Computer Science for All" program to empower a new generation of students in America with the proper computer science proficiency required to flourish in a digital economy. Computational thinking means thinking or solving problems like computer scientists. CT refers to thought processes required in understanding problems and formulating solutions. CT involves logic, assessment, patterns, automation, and generalization. Career readiness can be integrated into academic environments in multiple ways.

The "algoRithms" part of CT has also been referred to as the "fourth R", where the others are Reading, wRiting, and aRithmetic.

Computational education

3D design of cubicle desks to get computers to the desk for a computational education

In K–12 education

Similar to Seymour Papert, Alan Perlis, and Marvin Minsky before, Jeannette Wing envisioned computational thinking becoming an essential part of every child's education. However, integrating computational thinking into the K–12 curriculum and computer science education has faced several challenges including the agreement on the definition of computational thinking, how to assess children's development in it, and how to distinguish it from other similar "thinking" like systems thinking, design thinking, and engineering thinking. Currently, computational thinking is broadly defined as a set of cognitive skills and problem solving processes that include (but are not limited to) the following characteristics (but there are arguments that few, if any, of them belong to computing specifically, instead of being principles in many fields of science and engineering).

  • Using abstractions and pattern recognition to represent the problem in new and different ways
  • Logically organizing and analyzing data
  • Breaking the problem down into smaller parts
  • Approaching the problem using programmatic thinking techniques such as iteration, symbolic representation, and logical operations
  • Reformulating the problem into a series of ordered steps (algorithmic thinking)
  • Identifying, analyzing, and implementing possible solutions with the goal of achieving the most efficient and effective combination of steps and resources
  • Generalizing this problem-solving process to a wide variety of problems

Current integration of computational thinking into the K–12 curriculum comes in two forms: in computer science classes directly or through the use and measure of computational thinking techniques in other subjects. Teachers in Science, Technology, Engineering, and Mathematics (STEM) focused classrooms that include computational thinking, allow students to practice problem-solving skills such as trial and errorValerie Barr and Chris Stephenson describe computational thinking patterns across disciplines in a 2011 ACM Inroads article However Conrad Wolfram has argued that computational thinking should be taught as a distinct subject.

There are online institutions that provide a curriculum, and other related resources, to build and strengthen pre-college students with computational thinking, analysis and problem-solving.

Center for Computational Thinking

Carnegie Mellon University in Pittsburgh has a Center for Computational Thinking. The Center's major activity is conducting PROBEs or PROBlem-oriented Explorations. These PROBEs are experiments that apply novel computing concepts to problems to show the value of computational thinking. A PROBE experiment is generally a collaboration between a computer scientist and an expert in the field to be studied. The experiment typically runs for a year. In general, a PROBE will seek to find a solution for a broadly applicable problem and avoid narrowly focused issues. Some examples of PROBE experiments are optimal kidney transplant logistics and how to create drugs that do not breed drug-resistant viruses.

Criticism

The concept of computational thinking has been criticized as too vague, as it's rarely made clear how it is different from other forms of thought. The inclination among computer scientists to force computational solutions upon other fields has been called "computational chauvinism". Some computer scientists worry about the promotion of computational thinking as a substitute for a broader computer science education, as computational thinking represents just one small part of the field. Others worry that the emphasis on computational thinking encourages computer scientists to think too narrowly about the problems they can solve, thus avoiding the social, ethical and environmental implications of the technology they create. In addition, as nearly all CT research is done in the US and Europe, it is not certain how well those educational ideas work in other cultural contexts.

A 2019 paper argues that the term "computational thinking" (CT) should be used mainly as a shorthand to convey the educational value of computer science, hence the need of teaching it in school. The strategic goal is to have computer science recognized in school as an autonomous scientific subject more than trying to identify "body of knowledge" or "assessment methods" for CT. Particularly important is to stress the fact that the scientific novelty associated with CT is the shift from the "problem solving" of mathematics to the "having problem solved" of computer science. Without the "effective agent", who automatically executes the instructions received to solve the problem, there would be no computer science, but just mathematics. Another criticism in the same paper is that focusing on "problem solving" is too narrow, since "solving a problem is just an instance of a situation where one wants to reach a specified goal". The paper therefore generalizes the original definitions by Cuny, Snyder, and Wing and Aho as follows: "Computational thinking is the thought processes involved in modeling a situation and specifying the ways an information-processing agent can effectively operate within it to reach an externally specified (set of) goal(s)."

Many definitions of CT describe it only at skill level because the momentum behind its growth comes from its promise to boost STEM education. And, the latest movement in STEM education is based on suggestions (by learning theories) that we teach students experts' habits of mind. So, whether it is computational thinking, scientific thinking, or engineering thinking, the motivation is the same and the challenge is also the same: teaching experts' habits of mind to novices is inherently problematic because of the prerequisite content knowledge and practice skills needed to engage them in the same thinking processes as the experts. Only when we link the experts' habits of mind to fundamental cognitive processes can we then narrow their skill-sets down to more basic competencies that can be taught to novices. There have been only a few studies that actually address the cognitive essence of CT. Among those, Yasar (Communications of ACM, Vol. 61, No. 7, July 2018) describes CT as thinking that is generated/facilitated by a computational device, be it biological or electronic. Accordingly, everyone employs CT, not just computer scientists, and it can be improved via education and experience.

Computational logic and human thinking

Computational logic is an approach to computing that includes both computational thinking and logical thinking. It is based on a view of computing as the application of general-purpose logical reasoning to domain-specific knowledge expressed in logical terms.

Teaching materials for computational logic as a computer language for children were developed in the early 1980s. University level texts for non-computing students were developed in the early 2010s. More recently, a variety of new teaching materials have been developed to bridge the gap between STEM and non-STEM academic disciplines.

Subatomic particle

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