Have a deep view into what people are curious about.

Cupellation is a refining process in metallurgy where ores or alloyed metals are treated under very high temperatures and have controlled operations to separate noble metals, like gold and silver, from base metals, like lead, copper, zinc, arsenic, antimony, or bismuth, present in the ore. The process is based on the principle that precious metals do not oxidise or react chemically, unlike the base metals, so when they are heated at high temperatures, the precious metals remain apart, and the others react, forming slags or other compounds.

Since the Early Bronze Age, the process was used to obtain silver from smelted lead ores. By the Middle Ages and the Renaissance, cupellation was one of the most common processes for refining precious metals. By then, fire assays were used for assaying minerals, that is, testing fresh metals such as lead and recycled metals to know their purity for jewellery and coin making. Cupellation is still in use today.

🔗 Philosophy 🔗 Philosophy/Logic 🔗 Philosophy/Epistemology

The theory of belief functions, also referred to as evidence theory or Dempster–Shafer theory (DST), is a general framework for reasoning with uncertainty, with understood connections to other frameworks such as probability, possibility and imprecise probability theories. First introduced by Arthur P. Dempster in the context of statistical inference, the theory was later developed by Glenn Shafer into a general framework for modeling epistemic uncertainty—a mathematical theory of evidence. The theory allows one to combine evidence from different sources and arrive at a degree of belief (represented by a mathematical object called belief function) that takes into account all the available evidence.

In a narrow sense, the term Dempster–Shafer theory refers to the original conception of the theory by Dempster and Shafer. However, it is more common to use the term in the wider sense of the same general approach, as adapted to specific kinds of situations. In particular, many authors have proposed different rules for combining evidence, often with a view to handling conflicts in evidence better. The early contributions have also been the starting points of many important developments, including the transferable belief model and the theory of hints.

🔗 Human rights 🔗 History 🔗 China 🔗 Economics 🔗 Politics 🔗 Socialism 🔗 Anthropology 🔗 Culture

The Cultural Revolution, formally the Great Proletarian Cultural Revolution, was a sociopolitical movement in China from 1966 until 1976. Launched by Mao Zedong, Chairman of the Communist Party of China (CPC), its stated goal was to preserve Chinese Communism by purging remnants of capitalist and traditional elements from Chinese society, and to re-impose Mao Zedong Thought (known outside China as Maoism) as the dominant ideology in the CPC. The Revolution marked Mao's return to the central position of power in China after a period of less radical leadership to recover from the failures of the Great Leap Forward, which led to approximately 30 million deaths in the Great Chinese Famine only five years prior.

Launching the movement in May 1966 with the help of the Cultural Revolution Group, Mao soon called on young people to "bombard the headquarters", and proclaimed that "to rebel is justified". In order to eliminate his rivals within the CPC and in schools, factories, and government institutions, Mao charged that bourgeois elements had infiltrated the government and society with the aim of restoring capitalism. He insisted that revisionists be removed through violent class struggle, to which China's youth, as well as urban workers, responded by forming Red Guards and "rebel groups" around the country. They would begin to hold struggle sessions regularly, and grab power from local governments and CPC branches, eventually establishing the revolutionary committees in 1967. The groups often split into rival factions, however, becoming involved in 'violent struggles' (simplified Chinese: 武斗; traditional Chinese: 武鬥; pinyin: wǔdòu), to which the People's Liberation Army had to be sent to restore order.

Having compiled a selection of Mao's sayings into the Little Red Book, which became a sacred text for Mao's personality cult, Lin Biao, Vice Chairman of the CPC, was written into the constitution as Mao's successor. In 1969, Mao suggested the end of the Cultural Revolution. However, the Revolution's active phase would last until at least 1971, when Lin Biao, accused of a botched coup against Mao, fled and died in a plane crash. In 1972, the Gang of Four rose to power and the Cultural Revolution continued. After Mao's death and the arrest of the Gang of Four in 1976, the Cultural Revolution finally came to an end.

The Cultural Revolution damaged China's economy and traditional culture, with an estimated death toll ranging from hundreds of thousands to 20 million. Beginning with the Red August of Beijing, massacres took place across China, including the Guangxi Massacre, in which massive cannibalism also occurred; the Inner Mongolia incident; the Guangdong Massacre; the Yunnan Massacres; and the Hunan Massacres. Red Guards destroyed historical relics and artifacts, as well as ransacking cultural and religious sites. The 1975 Banqiao Dam failure, one of the world's greatest technological catastrophes, also occurred during the Cultural Revolution. Meanwhile, tens of millions of people were persecuted: senior officials, most notably Chinese president Liu Shaoqi, along with Deng Xiaoping, Peng Dehuai, and He Long, were purged or exiled; millions were accused of being members of the Five Black Categories, suffering public humiliation, imprisonment, torture, hard labor, seizure of property, and sometimes execution or harassment into suicide; intellectuals were considered the "Stinking Old Ninth" and were widely persecuted—notable scholars and scientists such as Lao She, Fu Lei, Yao Tongbin, and Zhao Jiuzhang were killed or committed suicide. Schools and universities were closed with the college entrance exams cancelled. Over 10 million urban intellectual youths were sent to the countryside in the Down to the Countryside Movement.

In 1978, Deng Xiaoping became the new paramount leader of China and started the "Boluan Fanzheng" program which gradually dismantled the Maoist policies associated with the Cultural Revolution, and brought the country back to order. Deng then began a new phase of China by initiating the historic Reforms and Opening-Up program. In 1981, the Communist Party of China declared that the Cultural Revolution was "responsible for the most severe setback and the heaviest losses suffered by the Party, the country, and the people since the founding of the People's Republic."

🔗 Physics 🔗 Skepticism

Implicate order and explicate order are ontological concepts for quantum theory coined by theoretical physicist David Bohm during the early 1980s. They are used to describe two different frameworks for understanding the same phenomenon or aspect of reality. In particular, the concepts were developed in order to explain the bizarre behavior of subatomic particles which quantum physics struggles to explain.

In Bohm's Wholeness and the Implicate Order, he used these notions to describe how the appearance of such phenomena might appear differently, or might be characterized by, varying principal factors, depending on contexts such as scales. The implicate (also referred to as the "enfolded") order is seen as a deeper and more fundamental order of reality. In contrast, the explicate or "unfolded" order include the abstractions that humans normally perceive. As he wrote,

In the enfolded [or implicate] order, space and time are no longer the dominant factors determining the relationships of dependence or independence of different elements. Rather, an entirely different sort of basic connection of elements is possible, from which our ordinary notions of space and time, along with those of separately existent material particles, are abstracted as forms derived from the deeper order. These ordinary notions in fact appear in what is called the "explicate" or "unfolded" order, which is a special and distinguished form contained within the general totality of all the implicate orders (Bohm 1980, p. xv).

🔗 International relations 🔗 History 🔗 Disaster management 🔗 Medicine 🔗 Viruses 🔗 Lists 🔗 History of Science

This article is a list of deaths caused by an infectious disease. Widespread non-communicable diseases such as cardiovascular disease and cancer are not included.

🔗 Philosophy 🔗 Philosophy/Philosophy of mind

The hard problem of consciousness is the problem of explaining why and how sentient organisms have qualia or phenomenal experiences—how and why it is that some internal states are subjective, felt states, such as heat or pain, rather than merely nonsubjective, unfelt states, as in a thermostat or a toaster. The philosopher David Chalmers, who introduced the term "hard problem" of consciousness, contrasts this with the "easy problems" of explaining the ability to discriminate, integrate information, report mental states, focus attention, and so forth. Easy problems are (relatively) easy because all that is required for their solution is to specify a mechanism that can perform the function. That is, regardless of how complex or poorly understood the phenomena of the easy problems may be, they can eventually be understood by relying entirely on standard scientific methodologies. Chalmers claims that the problem of experience is distinct from this set and will "persist even when the performance of all the relevant functions is explained".

The existence of a "hard problem" is controversial. It has been accepted by philosophers of mind such as Joseph Levine, Colin McGinn, and Ned Block and cognitive neuroscientists such as Francisco Varela, Giulio Tononi, and Christof Koch. However, its existence is disputed by philosophers of mind such as Daniel Dennett, Massimo Pigliucci, and Keith Frankish and cognitive neuroscientists such as Stanislas Dehaene and Bernard Baars.

🔗 Languages 🔗 Melanesia 🔗 Melanesia/Papua New Guinea

Manam is a Kairiru–Manam language spoken mainly on the volcanic Manam Island, northeast of New Guinea.

🔗 Philosophy 🔗 Philosophy/Logic 🔗 Philosophy/Philosophy of mind

Bonini's paradox, named after Stanford business professor Charles Bonini, explains the difficulty in constructing models or simulations that fully capture the workings of complex systems (such as the human brain).

🔗 Video games

MIDI Maze is a networked first-person shooter for the Atari ST developed by Xanth Software F/X and released in 1987 by Hybrid Arts. The game takes place in a maze of untextured walls. The world animates smoothly as the player turns, much like the earlier Wayout, instead of only permitting 90 degree changes of direction. It has been suggested that MIDI Maze, using the built-in MIDI ports of the Atari ST for networking, introduced the concept of deathmatch combat. The game found a wider audience on the Game Boy as Faceball 2000.

The original MIDI Maze team consisted of James Yee as the business manager, Michael Park as the graphic and networking programmer, and George Miller writing the AI and drone logic.

🔗 Law 🔗 Lists

A 999-year lease, under historic common law, is an essentially permanent lease of property. The lease locations are mainly in Britain, its former colonies, and the Commonwealth.

A former colony, the Republic of Mauritius (The Raphael Fishing Company Ltd v. The State of Mauritius & Anor (Mauritius) [2008] UKPC 43 (30 July 2008)) established legal precedent on 30 July 2008 in respect of a 'permanent lease' on St. Brandon.