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πŸ”— The Opium of the Intellectuals

πŸ”— Books

The Opium of the Intellectuals (French: L'Opium des intellectuels) is a book written by Raymond Aron and published in 1955. It was first published in an English translation in 1957.

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πŸ”— Vulcan Salute (Handshake Alternative, U+1F596)

πŸ”— Popular Culture πŸ”— Star Trek

The Vulcan salutation is a hand gesture popularized by the 1960s television series Star Trek. It consists of a raised hand with the palm forward and the thumb extended, while the fingers are parted between the middle and ring finger.

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πŸ”— Whataboutism

πŸ”— United States πŸ”— International relations πŸ”— Soviet Union πŸ”— Russia πŸ”— Politics πŸ”— Media πŸ”— Journalism

Whataboutism, also known as whataboutery, is a variant of the tu quoque logical fallacy that attempts to discredit an opponent's position by charging them with hypocrisy without directly refuting or disproving their argument. It is particularly associated with Soviet and Russian propaganda. When criticisms were leveled at the Soviet Union during the Cold War, the Soviet response would often be "What about..." followed by an event in the Western world. As Garry Kasparov noted, it is a word that was coined to describe the frequent use of a rhetorical diversion by Soviet apologists and dictators, who would counter charges of their oppression, "massacres, gulags, and forced deportations" by invoking American slavery, racism, lynchings, etc. It has been adopted by other politicians and countries.

πŸ”— Von Neumann Universal Constructor

πŸ”— Mathematics

John von Neumann's universal constructor is a self-replicating machine in a cellular automata (CA) environment. It was designed in the 1940s, without the use of a computer. The fundamental details of the machine were published in von Neumann's book Theory of Self-Reproducing Automata, completed in 1966 by Arthur W. Burks after von Neumann's death.

Von Neumann's goal was to specify an abstract machine which, when run, would replicate itself. In his design, the machine consists of three parts: a 'blueprint' for itself, a mechanism that can read any blueprint and construct the machine (sans blueprint) specified by that blueprint, and a 'copy machine' that can make copies of any blueprint. After the mechanism has been used to construct the machine specified by the blueprint, the copy machine is used to create a copy of that blueprint, and this copy is placed into the new machine, resulting in a working replication of the original machine. Some machines will do this backwards, copying the blueprint and then building a machine.

To define his machine in more detail, von Neumann invented the concept of a cellular automaton. The one he used consists of a two-dimensional grid of cells, each of which can be in one of 29 states at any point in time. At each timestep, each cell updates its state depending on the states of the surrounding cells at the prior timestep. The rules governing these updates are identical for all cells.

The universal constructor is a certain pattern of cell states in this cellular automaton. It contains one line of cells that serve as a 'tape', encoding a sequence of instructions that serve as a 'blueprint' for the machine. The machine reads these instructions one by one and performs the corresponding actions. The instructions direct the machine to use its 'construction arm' to build a copy of the machine, without tape, at some other location in the cell grid. The tape can't contain instructions to build an equally long tape, just as a container can't contain a container of the same size. Therefore, the machine contains a separate 'copy machine' which reads the tape and places a copy into the newly constructed machine. The resulting new machine and tape is identical to the old one, and it proceeds to replicate again.

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πŸ”— Cheeger constant as a measure of β€œbottleneckedness”

πŸ”— Computing πŸ”— Mathematics πŸ”— Computing/Networking

In mathematics, the Cheeger constant (also Cheeger number or isoperimetric number) of a graph is a numerical measure of whether or not a graph has a "bottleneck". The Cheeger constant as a measure of "bottleneckedness" is of great interest in many areas: for example, constructing well-connected networks of computers, card shuffling. The graph theoretical notion originated after the Cheeger isoperimetric constant of a compact Riemannian manifold.

The Cheeger constant is named after the mathematician Jeff Cheeger.

πŸ”— Three-Domain System

πŸ”— Biology πŸ”— Evolutionary biology πŸ”— Tree of Life

The three-domain system is a biological classification introduced by Carl Woese et al. in 1990 that divides cellular life forms into archaea, bacteria, and eukaryote domains. In particular, it emphasizes the separation of prokaryotes into two groups, originally called Eubacteria (now Bacteria) and Archaebacteria (now Archaea). Woese argued that, on the basis of differences in 16S rRNA genes, these two groups and the eukaryotes each arose separately from an ancestor with poorly developed genetic machinery, often called a progenote. To reflect these primary lines of descent, he treated each as a domain, divided into several different kingdoms. Woese initially used the term "kingdom" to refer to the three primary phylogenic groupings, and this nomenclature was widely used until the term "domain" was adopted in 1990.

Parts of the three-domain theory have been fiercly challenged by scientists such as Radhey S. Gupta, who argues that the primary division within prokaryotes should be between those surrounded by a single membrane, and those with two membranes.

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πŸ”— Endling

πŸ”— Extinction

An endling is the last known individual of a species or subspecies. Once the endling dies, the species becomes extinct. The word was coined in correspondence in the scientific journal Nature. Alternative names put forth for the last individual of its kind include ender and terminarch.

The word relict may also be used, but usually refers to a population, rather than an individual, that is the last of a species.

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πŸ”— Autodidacticism

πŸ”— Psychology πŸ”— Education πŸ”— Homeschooling πŸ”— Alternative education

Autodidacticism (also autodidactism) or self-education (also self-learning and self-teaching) is education without the guidance of masters (such as teachers and professors) or institutions (such as schools). Generally, an autodidact is an individual who chooses the subject they will study, their studying material, and the studying rhythm and time. An autodidact may or may not have formal education, and their study may be either a complement or an alternative to formal education. Many notable contributions have been made by autodidacts.

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πŸ”— Boids

πŸ”— Computer science

Boids is an artificial life program, developed by Craig Reynolds in 1986, which simulates the flocking behaviour of birds. His paper on this topic was published in 1987 in the proceedings of the ACM SIGGRAPH conference. The name "boid" corresponds to a shortened version of "bird-oid object", which refers to a bird-like object. Incidentally, "boid" is also a New York Metropolitan dialect pronunciation for "bird".

As with most artificial life simulations, Boids is an example of emergent behavior; that is, the complexity of Boids arises from the interaction of individual agents (the boids, in this case) adhering to a set of simple rules. The rules applied in the simplest Boids world are as follows:

  • separation: steer to avoid crowding local flockmates
  • alignment: steer towards the average heading of local flockmates
  • cohesion: steer to move towards the average position (center of mass) of local flockmates

More complex rules can be added, such as obstacle avoidance and goal seeking.

The basic model has been extended in several different ways since Reynolds proposed it. For instance, Delgado-Mata etΒ al. extended the basic model to incorporate the effects of fear. Olfaction was used to transmit emotion between animals, through pheromones modelled as particles in a free expansion gas. Hartman and Benes introduced a complementary force to the alignment that they call the change of leadership. This steer defines the chance of the boid to become a leader and try to escape.

The movement of Boids can be characterized as either chaotic (splitting groups and wild behaviour) or orderly. Unexpected behaviours, such as splitting flocks and reuniting after avoiding obstacles, can be considered emergent.

The boids framework is often used in computer graphics, providing realistic-looking representations of flocks of birds and other creatures, such as schools of fish or herds of animals. It was for instance used in the 1998 video game Half-Life for the flying bird-like creatures seen at the end of the game on Xen, named "boid" in the game files.

The Boids model can be used for direct control and stabilization of teams of simple Unmanned Ground Vehicles (UGV) or Micro Aerial Vehicles (MAV) in swarm robotics. For stabilization of heterogeneous UAV-UGV teams, the model was adapted for using onboard relative localization by Saska etΒ al.

At the time of proposal, Reynolds' approach represented a giant step forward compared to the traditional techniques used in computer animation for motion pictures. The first animation created with the model was Stanley and Stella in: Breaking the Ice (1987), followed by a feature film debut in Tim Burton's film Batman Returns (1992) with computer generated bat swarms and armies of penguins marching through the streets of Gotham City.

The boids model has been used for other interesting applications. It has been applied to automatically program Internet multi-channel radio stations. It has also been used for visualizing information and for optimization tasks.

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  • "Boids" | 2024-02-28 | 15 Upvotes 3 Comments
  • "Boids" | 2020-03-28 | 391 Upvotes 80 Comments

πŸ”— The 480

πŸ”— Novels

The 480 is a political fiction novel by Eugene Burdick (1964).

The plot evolves around the political turmoil after John F. Kennedy assassination in 1963. In the novel, a fictitious charismatic character, John Thatch, an engineer, is seeking nomination for the Republican Party candidate at 1964 presidential elections. He is described as being contaminated with the "political virus". A handful of political professionals are promoting his nomination, in confrontation with the Party establishment. There exist apparent parallels between Thatch and Henry Cabot Lodge, Jr., a write-in hero at New Hampshire primary.

The novel criticizes the socio-political effects on society at large from the use of computers to run massive simulations, which predict the public reaction to certain (proposed) political moves before implementing them. Such simulations make it easy to manipulate the public consciousness.

The "480" in the title denotes the number of groups (by party affiliation, socioeconomic status, location, origin, etc.) that the computer simulation uses to classify the American electorate. The full list of these is reproduced in the Appendix, claimed by the author to be the true list used by the Simulmatics Corporation (real name) in Senator John F. Kennedy's Presidential campaign in 1960. The cover features an IBM 5081 punched card.

The Simulmatics Corporation was created by MIT Professor Ithiel de Sola Pool, who provided a non-fiction backup to "The 480" in "Candidates, Issues, and Strategies: A Computer Simulation of the 1960 Presidential Election," MIT Press, 1964 (with co-authors Robert P. Abelson and Samuel L. Popkin). They built their model from 130,000 archived interviews in Gallup and Roper polls over a ten-year period. Based on its output, they advised Kennedy that he would benefit from a strong civil rights stand and that he had nothing to lose, and much to gain, by attacking religious bigotry and dealing frankly with his Catholicism.

The 480 has been cited as prefiguring the effect of modern social media and data gathering on politics.

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