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Black tie

Black tie is a semi-formal Western dress code for evening events, originating in British and North American conventions for attire in the 19th century. In British English, the dress code is often referred to synecdochically by its principal element for men, the dinner suit or dinner jacket. In American English, the equivalent term tuxedo (or tux) is common. The dinner suit is a black, midnight blue or white two- or three-piece suit, distinguished by satin or grosgrain jacket lapels and similar stripes along the outseam of the trousers. It is worn with a white dress shirt with standing or turndown collar and link cuffs, a black bow tie, typically an evening waistcoat or a cummerbund, and black patent leather dress shoes or court pumps. Accessories may include a semi-formal homburg, bowler, or boater hat. For women, an evening gown or other fashionable evening attire may be worn.

The first dinner jacket is traditionally traced to 1865 on the then Prince of Wales, later King Edward VII (1841–1910). The late 19th century saw gradual introduction of the lounge jacket without tails as a less formal and more comfortable leisure alternative to the frock coat. Similarly, the shorter dinner jacket evolved as a less formal alternative to the dress coat out of the informal smoking jacket, itself derived from the banyan. Thus in many non-English languages, a dinner jacket is still known as the false friend "smoking". In American English, its synonym "tuxedo" was derived from the village of Tuxedo Park in New York State, where it was introduced in 1886 following the example of Europeans. Following the counterculture of the 1960s, black tie has increasingly replaced white tie for more formal settings in the United States, along with cultures influenced by American culture.

Traditionally worn only for events after 6 p.m., black tie is less formal than white tie but more formal than informal or business dress. As semi-formal, black tie are worn for dinner parties (public, fraternities, private) and sometimes even to balls and weddings, although etiquette experts discourage wearing of black tie for weddings. Traditional semi-formal day wear equivalent is black lounge suit. Supplementary semi-formal alternatives may be accepted for black tie: mess dress uniform, religious clothing (such as cassock), folk costumes (such as highland dress), etc.

Name
Dinner jacket in the context of menswear first appeared in the United Kingdom around 1887 and in the United States around 1889. In the 1960s it became associated in the United States with white or coloured jackets specifically. In modern British English, dinner jacket may be abbreviated to simply a "DJ".

Tuxedo in the context of menswear originated in the United States around 1888. It was named after Tuxedo Park, a Hudson Valley enclave for New York's social elite where it was often seen in its early years. The term was capitalized until the 1930s and traditionally referred only to a white jacket. When the jacket was later paired with its own unique trousers and accessories in the 1900s the term began to be associated with the entire suit. Sometimes it is shortened to "tux".

In French, Italian, Portuguese, German, Polish, Russian, Spanish, Persian, Turkish, and other European languages the style is referred to with the pseudo-anglicism smoking (esmoquin). This generic colloquialism is a false friend deriving from its similarity with the 19th century smoking jacket. In French the dress code may also be called "cravate noire", a term that is sometimes adopted directly into English.

The suit with accompanying accessories is sometimes nicknamed a monkey suit and, since 1918, soup and fish – a term derived from the sort of food thought to be served at black tie dinners.

British origins in the 19th century
In the 1860s, the increasing popularity of outdoor activities among the middle and upper classes of the UK led to a corresponding increase in the popularity of the then casual lounge suit as a country alternative to the more formal day wear frock coat that was traditionally worn in town. Men also sought a similar alternative to the formal evening tailcoat, then known as a "dress coat", worn every evening.

The earliest record of a tailless coat being worn with evening wear is an 1865 midnight blue smoking jacket in silk with matching trousers ordered by the Prince of Wales, later Edward VII of the United Kingdom, from Savile Row tailors Henry Poole & Co. The smoking jacket was tailored for use at Sandringham, the British Royal Family's informal country estate. Henry Poole never saw his design become known as a dinner jacket or cross the Atlantic and be called a tuxedo over there; he died in 1876 leaving behind a well-respected business to be run by his cousin Samuel Cundey.

Other accounts of the Prince's experimentation appear around 1885, referring variously to "a garment of many colours, such as was worn by our ancestors" and "short garments coming down to the waist and made on the model of the military men's jackets". The suit jacket with tailcoat finishes, as is most commonly known, was first described around the same time and often associated with Cowes, a seaside resort in southern England and centre of British yachting that was closely associated with the Prince. It was originally intended for warm weather use but soon spread to informal or stag winter occasions. As it was simply an evening tailcoat substitute, it was worn with all the same accoutrements as the tailcoat, including the trousers. As such, in these early days, black tie, in contrast to formal white tie, was considered informal wear.

In the following decades of the Victorian era, the style became known as a dinner jacket: a fashionable, formal alternative for the tailcoat which men of the upper classes wore every evening. Thus it was worn with the standard accompaniments for the evening tailcoat at the time: matching trousers, white or black waistcoat, white bow tie, white detachable wing-collar formal shirt, and black formal shoes. Lapels were often faced or edged in silk or satin in varying widths. In comparison with a full dress such as a cutaway tailcoat, etiquette guides declared dinner jacket inappropriate for wear in mixed company, meaning together with ladies.

During the Edwardian era, the practice of wearing a black waistcoat and black bow tie with a dinner jacket became the convention, establishing the basis of the current black tie and white tie dress codes. The dinner jacket was also increasingly accepted at less formal evening occasions such as warm-weather gatherings or intimate dinners with friends.

After World War I, the dinner jacket became established as a semi-formal evening wear, while the evening tailcoat was limited to the most formal or ceremonial occasions. During this interwar period, double-breasted jackets, turndown-collar shirts and cummerbunds became popular for black tie evenings as white jackets were experimented with in warm weather. Since then, black tie is often referred to as being semi-formal.

In the decades following the World War II, black tie became special occasion attire rather than standard evening wear. In the 1950s, some experimented with coloured and patterned jackets, cummerbunds and bow ties. The 1960s and 1970s saw the colour palette move from muted to bright day-glow and pastel, as well as ruffled-placket shirts as lapels got wider and piping was revived. The 1980s and 1990s saw a return to traditional styles, with black jackets and trousers again becoming nearly universal. Some insist the 21st century has seen increased variation and a relaxation of previous strict standards; midnight blue once again became popular and lapel facings were sometimes reduced to wide edging.

Introduction to the United States
The earliest references to a dress coat substitute in America are from the summer and fall of 1886 and, like the British references from this time, vary between waist-length mess-jacket style and the conventional suit jacket style. The most famous reference originates from Tuxedo Park, an upstate New York countryside enclave for Manhattan's wealthiest citizens. A son of one of the community's founders, Griswold Lorillard, and his friends were widely reported in society columns for showing up at the club's first Autumn Ball in October 1886 wearing "a tailless dress coat". Although it is not known whether this garment was a mess jacket or a conventional dinner jacket, it has no doubt cemented the tailcoat substitute's association with Tuxedo Park in the mind of the public.

An essay in the Tuxedo Park archives attributes the jacket's importation to America to resident James Brown Potter, a merchant banker who had worked in London for Brown Brothers. However, this claim for Potter cannot be verified through independent sources. Period newspaper accounts indicate that at first the jacket was worn by young mavericks to gatherings considered strictly formal. This led the American establishment to reject it out of hand. It was only by 1888 that polite society accepted its role solely as summer and informal evening substitute, at which point it became very popular.

20th century changes
The earliest dinner jackets were of the same black material as the dress coat with one, two or no buttons, and a shawl collar faced in satin or ribbed silk. By the turn of the twentieth century, the peaked lapel was equally popular and the one-button model had become standard. When trousers were sold with the jacket they were of the same material. Edwardian dandies often opted for Oxford grey or a very dark blue for their evening wear.

By World War I, the grey option had fallen out of favor but the "midnight blue" alternative became increasingly popular and rivalled black by the mid-1930s. Notch lapels, imported from the ordinary business suit, were a brief vogue in the 1920s. A single stripe of braid covering the outseam on each leg was an occasional variation at first but became standard by the 1930s. At this time double-breasted jackets and white jackets became popular for wear in hot weather.

Colour, texture and pattern became increasingly popular in warm-weather jackets in the 1950s. In the 1960s, these variations became increasingly common regardless of season or climate. Notch lapels were once again a fad. By the 1970s, mass-market retailers began offering white and coloured versions of the entire suit to its rental customers. The 1980s vogue for nostalgic and retro styles returned evening wear to its black tone. Notch lapels returned for good in the 1980s, and in the 1990s tuxedo jackets increasingly took on other traits of the business suit, such as two- and three-button styling, flap pockets, and centre vents. These trends have continued into the early 21st century, and midnight blue is now once again a popular alternative.

Composition
The dinner suit's accompaniments have also evolved over time. The most traditional interpretations of these elements – dress shirt, low cut waistcoat (in the "V" or "U" shape), black bow tie, oxford dress shoes – are incorporated in the black tie dress code.

Unlike white tie, which is very strictly regulated, black tie ensembles can display more variation. More extensively, the traditional components for men are:

 * A dinner jacket, also called a tuxedo jacket in the United States, is primarily made of black or midnight blue wool. Dinner jackets in an off-white color are also considered appropriate for some occasions, but it traditionally associated with warmer climates and differs from other dinner jackets in that it is self-faced and can be made of fabrics including linen and cotton. Silk jacket lapels and facings, usually grosgrain or satin, are a defining element of the jacket and can be seen on every type of lapel. The dinner jacket may have a peaked lapel, a shawl lapel, or a notched lapel, with some fashion stylists and writers seeing shawl lapels as less formal and notched lapels as the least formal, despite the fact that they, like peaked and shawl, were used (though somewhat rarely) in some of the early forms of the garment.
 * Trousers with a single silk or satin braid covering the outer seams, uncuffed and worn with braces
 * A black low-cut waistcoat or a cummerbund
 * A white dress shirt, with a marcella or pleated bib being traditional, with double or "French" cuffs and a turndown collar. While the turndown is most appropriately semi-formal, the attached wing collar has been popular with American men since the 1980s. However, many style authorities argue that the attached version now typically offered is insubstantial with minuscule wings and inappropriately paired with soft pleated fronts.
 * A black silk bow tie matching the lapel facings
 * Shirt studs and cufflinks. Some classic etiquette authorities limit studs to stiff-front marcella shirts only and prescribe pearl buttons for soft-front models instead.
 * Black dress socks, usually of silk or fine wool. Some style guides recommend that the socks should come up to the knee.
 * Black shoes – traditionally patent leather court shoes or pumps; now often highly polished or patent leather Oxford dress shoes instead, without brogueing

Jacket
The original and most formal model of dinner jacket is the single-breasted model. The typical black tie jacket is single-breasted with one button only, with jetted, or besom, pockets and is of black or midnight blue; usually of wool or a wool-mohair, or wool-polyester blend, although other materials, especially silk, are seen. Although other materials are used, the most appropriate and traditional for the dinner jacket are wool barathea or superfine herringbone. Double-breasted models have become less common, but are generally considered equally appropriate for most black tie occasions. Dinner jackets were commonly ventless before World War I, but in the 21st century come ventless, with side vents, or, less commonly, with centre vents. The ventless style is considered more formal, whilst the centre vent is the least formal. The lapels, traditionally pointed and shawl, are usually faced with silk in either a grosgrain or a satin weave, but can also be silk barathea. A notched lapel is usually considered more appropriate for a business suit than a dinner jacket but is commonly seen on inexpensive off the rack dinner jackets. According to the Black Tie Guide, the peaked lapel and shawl collar are equally authentic and correct, with the latter being slightly less formal. The buttons are covered in similarly coloured material to the main part of the jacket, which would typically be either self-faced or covered with the same material as the lapels. Some higher-end single-breasted jackets, both new and vintage, tend to be fastened with a link front closure which is visually similar to a cufflink; this traditional method of closure is common in the United Kingdom.

The double-besomed jetted or slit hip pocket is the only style understated enough to complement the dinner jacket. Flap pockets are not considered appropriate for formal attire's refined minimalism due to their busier and bulkier design, and some believe that they are simply an attempt by dinner jacket manufacturers to save money by using standard suit patterns, although sometimes they will trim the edges of a flap pocket so that the flap can be tucked in or removed if desired. Besom welts can be of self fabric or trimmed with the lapel's silk facing, though classic menswear scholar Nicholas Antongiavanni suggests that for the English this latter touch "is a sure sign of hired clothes". The dinner jacket also has a welt breast pocket to hold a pocket handkerchief, which is generally self-faced rather than covered with silk.

Emily Post, a resident of Tuxedo Park, New York, stated in 1909 that "[Tuxedos] can have lapels or be shawl-shaped, in either case they are to have facings of silk, satin or grosgrain". She later republished this statement in her 1922 book Etiquette, adding that only single-breasted jackets are appropriately called tuxedos. There is a fashion movement suggesting that a man's appearance when wearing the wider and higher peak lapel is superior to the narrower notch lapel.

White dinner jackets are often worn in warm climates. They are ivory in colour rather than pure white, and have self-faced lapels, i.e., made of the same fabric as the jacket, rather than silk-faced lapels. They are generally worn with the same types of shirts and accessories as black dinner jackets, though the turndown collar and cummerbund preferred to the wing collar or waistcoat. Similarly, the shawl lapel is more common in white dinner jackets. In the United Kingdom, the 20th-century etiquette was that white dinner jackets are never worn, even on the hottest day of summer, but are reserved for wear abroad. In the 21st century, white dinner jackets are frequently seen at weddings, formal beach events, and high-school proms, in the United States and at some concerts, famously for instance the Last Night of the Proms, in the United Kingdom. In tropical climates, such as in Imperial Burma, the desert fawn was historically used as the less formal colour. At one time, the civilian mess jacket was also an option in warmer climates.

It is generally considered inappropriate for a man to remove his jacket during a formal social event, but when hot weather and humidity dictate, the ranking man of the royal family or the guest of honour may give men permission by noticeably taking off his jacket. In anticipated hot weather, Red Sea rig is specified in the invitation, although this dress is esoteric in civilian circles, and is particular to certain expatriate communities.

Black bow tie
Traditionally, the only neckwear appropriate is the black bow tie that is a self-tie and always matches the lapel facing of the dinner jacket and braiding of the trouser seams. The bow tie is tied using a common shoelace knot, which is also called the bow knot for that reason.

Trousers
Black tie trousers traditionally have no turn-ups, also called cuffs in American English, or belt loops. The outer seams are usually decorated with a single braid of silk or a material that matches or complements the lapel facing. Traditionally, braces, called suspenders in US English, hidden by the waistcoat, are used to support the trousers. Belts are never worn with black tie trousers. Evening trousers may be flat-fronted or pleated, with pleats first coming into fashion in the 1930s. Whilst flat-fronted trousers have become more fashionable, pleated trousers may be considered more comfortable by men who have wider hips and a narrow waist.

Waist coverings
A waist covering is generally worn as part of a black tie ensemble. Either a low cut waistcoat or cummerbund may be worn, but never both at the same time. Although the English authority Debrett's consider that wearing a waistcoat is smart, they no longer consider either waist covering to be essential. The American authority, The Emily Post Institute, considers them to be an essential component of proper black tie attire. Waist coverings are not matched to wedding theme colours.

Waistcoat
A low cut waistcoat should be worn when wearing a single-breasted coat. The waistcoat plays an important part in black tie's refined minimalism by helping to conceal its working parts by discreetly covering the trousers' exposed waistband and the shirt bosom's bottom edge. Waistcoats come in the 'V' or rarer 'U' shape, in backless or fully backed versions, double- or single-breasted, with or without lapels. Single-breasted styles typically have three buttons, and double-breasted ones three or four rows. Before World War II, while black tie was still gaining acceptance, men would wear a white waistcoat, along with other details now associated primarily with white tie, such as stiff fronted shirts. However, this style, though increasingly viewed as an affectation, is still acceptable in the United States. The waistcoat may be made from either the same fabric as the dinner jacket, as is traditional, or the same silk as the jacket's lapels, which is more popular. When a waistcoat has lapels, they are faced in the same silk as those of the jacket; in this case it is considered more refined if the body is made from the same fabric as the jacket. The buttons may be self-faced or covered in the same silk as the lapels. Vintage waistcoats were sometimes closed with studs made from onyx or mother-of-pearl, which were often surrounded by a setting of silver or gold.

A waistcoat is never worn with a double-breasted jacket. Since this style of jacket is never unbuttoned, the waist of the trousers is never exposed, and therefore does not need to be covered, though before World War II an edge of the waistcoat was often shown between the jacket and shirt.

Cummerbund
A cummerbund may be worn with a dinner jacket in lieu of a waistcoat and, although it is considered slightly less formal, it is equally correct. It looks especially well with a shawl collar dinner jacket but may be worn in conjunction with peak lapels. The material of the cummerbund should be silk satin, grosgrain, also called faille, or barathea to match that of the bow tie. It features upward-facing folds, which were originally used to store theatre or opera tickets, and are now considered to be more decorative than functional. Just like the waistcoat, cummerbunds are not worn with a double-breasted jacket.

As the cummerbund is seen as an extension of the trousers, traditionally it is the same colour, i.e. black. However, the Black Tie Guide endorses deep and rich colours as a tasteful way to introduce some colour into an outfit that is otherwise monochromatic. Bright colours, such as those often worn by members of wedding parties, should be avoided and the bow tie must remain black in any case. Some higher quality models feature a hidden pocket and an elastic loop to fasten to the trousers.

Shirt
Dress shirts designed to be worn with black tie are sometimes called "tuxedo shirts" in American English. Traditionally, the shirt is white, has a bibbed front that is either marcella or pleated, a turndown collar, and double, or "french" cuffs. In the early-20th century, a piqué shirt with a detachable wing collar and single cuffs such as is worn with white tie was used, and in the 1960s and 1970s ruffled bibs were popular, but have since become uncommon. The wing collar originally disappeared in black tie after the 1920s when the appropriately semi-formal attached turndown collar shirt became preferred, but it has been popular with American men in a less substantial, attached form since the 1980s. However, many style authorities argue that the wing collar should remain the domain of white tie for aesthetic reasons. Etiquette maven Miss Manners is one of those who feel that while the bow tie's uncovered band is fine in a white-on-white scheme, "gentlemen with their black ties exposed all-around their necks look silly".

Although some style authorities consider the wing collar to be an acceptable option for black tie shirts, they are not worn with double cuffs or a pleated bib, and are better suited to the more formal single-breasted peak lapel jacket. They may feature a bib that is either marcella or starched and include stiff single cuffs secured with cufflinks, made of the same fabric as the bib; this type of shirt is exactly the same as one worn with white tie attire. The collar in this case is tall and stiff, which may be attached or detachable. When a full dress shirt is worn in this fashion, it is accompanied by the white marcella waistcoat ordinarily associated with white tie. Wearing white tie accessories in this manner is considered by many to be an affectation. Debrett's do not endorse the wing collar as being compatible with the black tie dress code.

The more formal marcella version of the shirt fastens with matching shirt studs. These are most commonly in silver or gold settings, featuring onyx or mother-of-pearl; various geometrical shapes are worn, e.g., circles, which are most common for studs, octagons, or rectangles, which are most common for cufflinks. There has been no consistent fashion preference for gold or silver, but studs with mother-of-pearl are more formal and therefore often associated with white tie. The soft-front pleated version of the shirt should be fastened with mother-of-pearl buttons, typically supplied with the shirt on a separate strip of fabric. Alternatively, a fly-front shirt, appropriate with both the marcella and pleated bibs, conceals the placket for a more minimalistic look.

There are several types of cufflinks that may be worn with black tie. The most formal and decorative are the double-panel type, which dress both sides of the cuff and are connected by a chain or link of metal; this model conceals the mechanism by which the cuff is secured. The most common, and least decorative, are the swivel bar type; whilst these are acceptable, they leave the inner side of the cuffs and mechanism exposed which is incongruous with formal dress.

Footwear
The most formal and traditional shoes are patent leather opera pumps, also called court shoes, decorated with grosgrain bows. The more popular alternative is the black lace-up Oxford shoe, in patent leather or calfskin, with a rounded plain toe. Brogueing or any other decorative patterns should never be seen on black tie footwear. Matte finish pumps are also seen. Shoes are almost invariably black and patent leather is considered more formal than matte finishes while pumps are considered more formal than lace-ups. Generally considered too informal for black tie are shoes with open lacing, such as the Derby shoe, called bluchers in American English. Notable alternatives include the black button boot, primarily of historical interest only, and the monogrammed Albert slipper which was originally worn only at home. Hosiery is black socks made from fine wool or silk.

Accessories
Most etiquette and fashion guides of the current decade recommend keeping colour touches and favouring a single colour, usually dark; muted reds, such as maroon, are a traditional choice.

Handkerchief: A handkerchief in linen traditionally, or silk, or cotton is usually worn in the breast pocket. Although precedents for tasteful exceptions exist, pocket squares are normally white, and may not match the waist covering or bow tie.

Boutonnière: A flower may be worn. Red and white carnation, blue cornflower, and rosebud have all been popular at times. In France, the boutonnière is usually a gardenia.

Outerwear: Black tie events do not involve outerwear and coats and gloves are no longer considered part of the dress code. However, etiquette for what to wear in public in transit to and from black tie occasions was stiffer in earlier eras and remain an option: Matching overcoats are usually black, charcoal, or dark blue, and traditionally of the Chesterfield style. A guards coat was also once popular, and a lighter topcoat can be worn in summer. Historically, an Inverness coat was also worn. Until the mid-20th century, gloves and scarves were always worn, and are still occasionally seen in grey leather and white silk, respectively. White kid gloves have never been standard with black tie, remaining exclusive to white tie dress.

Hat: The 20th-century standard hat for black tie was a black or midnight blue Homburg in winter, or straw boater in spring and summer. Fedoras were originally regarded as too informal but have become more common. Top hats were originally worn with black tie, but had been reserved to white tie and morning dress from World War I. In the 1960s, it became optional to wear a hat with black tie, while from the 1970s onwards hats became less common.

Decorations and orders: Military, civil, and organizational decorations are usually worn only to full dress events, generally of formal governmental or diplomatic significance. Miniature orders and awards are typically worn on the left lapel of the jacket, and neck badges, breast stars, and sashes are worn according to country-specific or organizational regulations. Unlike in white tie, where decorations are always permitted, the dress code will usually give some indication when decorations are to be worn with black tie.

Timepiece: Traditionally visible timepieces are not worn with formal evening dress, because timekeeping is not supposed to be considered a priority. Pocket watches are acceptable.

Women
Women's dress for black tie occasions has varied greatly throughout the years; traditionally it was:

 * A dinner length gown at the ankle or tea length gown below mid-calf, which is a sleeveless evening gown, often accompanied by:
 * A wrap or stole and
 * Gloves
 * Evening shoes

Other fashionable evening attire may be worn. Unlike the men's standard, the specifics of black tie for women are linked to whatever evening wear is currently in fashion. Today ladies' dress for black tie occasions covers a much wider level of formality ranging from just below the white tie standard to something more informal such as a little black dress. Specifically it can also include:
 * Evening shoes and
 * A ballgown, evening gown or cocktail dress. Cocktail dresses may be long or moderately short and need not be black.
 * In England, evening trousers with a palazzo cut are another acceptable option.

Still, while "black tie" dress code traditionally implies evening dress for women, in 1966 famous couturier Yves Saint Laurent proposed Le Smoking, a dinner suit designed for women. Most initial reactions to the collection were negative. The designer took bits and pieces from both men's suit and women's clothing and combined it with new ideas. As this dinner suit was designed for women, it was different from the normal male dinner suit. The collar was more feminine, as the shape and curve were more subtle. The waistline of the blouse was narrowed to show the body shape, and pants were adjusted to help elongate the leg. It pioneered long, minimalist, androgynous styles for women, as well as the female use of power suits and the pantsuit in modern-day society. Some described Saint Laurent's initiative as empowerment of women by giving them the option to wear clothes that were normally worn by men with influence and power. Fashion photography echoes the influence of this suit in shoots that feature androgynous models with slicked-back hair in a mannish three-piece suit, a style that was first popularized in photographs by Helmut Newton. This suit has continued to influence fashion designers' collections through the 2000s.

Social occasions
In traditional Western dress codes etiquette black tie is intended for men's evening wear. Traditionally in the 20th century black tie, in contrast to formal white tie, was considered informal. In the 21st century black tie is often referred to as being semi-formal.

Black tie is worn to private and public dinners, balls and parties. At the more formal end of the social spectrum, it has to a large extent replaced the more formal white tie. Once more common, white tie dress code is fairly rare, being reserved for only the most formal occasions. Black tie is traditionally worn only after six o'clock in the evening, or after sundown during winter months. Black tie's rough daytime equivalent is the stroller, which is less formal than morning dress because, as with black tie, it replaces the tailcoat with a lounge coat. Contrary to the trend seen in evening dress, the less formal stroller is now extraordinarily rare, whereas morning dress is still relatively common.

The most popular uses of the dinner suit in the United States in the early 21st century are for balls, galas, proms, cruise ship dinners and weddings. In these circumstances the dinner suit's styling and accessories are most commonly chosen according to the wearer's tastes. Less popular are black tie events, such as gala fundraisers, where men typically wear more traditional dinner suits and accessories as dictated by the dress code. They are also often worn by male musicians at concerts.

As a general rule boys do not wear dinner jackets much before they are 15 or dress coat before they are about 18.

Academia
Some British university debating societies, such as at Oxford, Durham and University College London conduct at least some of their debates in black tie. Notably, the Cambridge Union abolished the long-standing mandatory wearing of black tie at debates in 2002. The Irish Times hosts an annual black tie debating competition.

Learned societies, such as the Royal Aeronautical Society, may also follow a similar practice.

Black tie dinners and debates are held through the academic year by British university Conservative associations, such as those at Oxford, Cambridge, York, and Nottingham.

Opera and ballet
Historically, white tie was worn for the opera. Since the 20th century, however, black tie has been worn increasingly and today a dark lounge suit is generally acceptable. In the 21st century, many opera houses in the English-speaking world do not stipulate black tie. For example, neither the Royal Opera House nor the Sydney Opera House maintain a black tie dress code. Notwithstanding, black tie is customary at English country house operas, such as during the summer Festival at Glyndebourne. Black tie is also worn at a ballet or orchestra gala.

Cruise ships
At more formal dinners on cruise ships the dress code will typically be black tie although a dark lounge suit may be worn as a substitute. In 2013 Cunard, noted for its adherence to formal dress codes, relaxed its dress standards. Cunard requires one of a dinner jacket, a dark suit, formal national dress or military uniform for gentlemen diners on formal evenings. Similarly, the luxury cruise liner, Seabourn, stipulates either a dinner suit or a dark business suit on formal evenings.

Weddings
Black tie has been increasingly seen in the United States at weddings in place of the traditional morning dress. However, etiquette and clothing experts see the wearing of black tie before 6 p.m. as out of the ordinary. Prior to the late 1930s, black tie was even discouraged as too informal for evening weddings, with Amy Vanderbilt arguing that "no man should ever be caught in a church in a tuxedo". Emily Post would continue to argue in preference of white tie at evening weddings into the 1950s.

In the United Kingdom and the rest of Europe, although a minority accepts black tie at evening wedding receptions, including some Jewish weddings, it is seldom worn at church weddings or civil ceremonies where morning dress or a lounge suit is normally favoured.

Other than that, supplementary alternatives include local variations of white tie etiquette, such as highland dress in Scotland, if neither white tie nor black tie is preferred.

Magazines

 * Apparel Arts magazine, an account of 1930s fashion and style; some issues more relevant than others, such as those reproduced with comment at The London Lounge: Vol II. No. II and Vol I. No. III (numbering: London Lounge, not original)

Websites

 * The Emily Post Institute provides a breakdown of traditional categories of progressing formality in dress for men and women.
 * Debrett's is the most prominent British authority on etiquette, which discusses the elements of black tie.

title: Black tie


text:
Richard Somers

Richard Somers (September 15, 1778 – September 4, 1804) was an officer of the United States Navy, killed during an assault on Tripoli during the First Barbary War.

Early career
Born at Great Egg Harbor, New Jersey, he attended the Episcopal Academy in Philadelphia with future naval heroes Stephen Decatur and Charles Stewart. He was appointed midshipman on April 23, 1797, and served in the West Indies during the Quasi-War with France on the frigate United States with Decatur and Stewart, a ship commanded by Captain John Barry. He was promoted to lieutenant on May 21, 1799.

In 1800, Somers fought three duels on the same day with multiple opponents because they accused him of cowardice for failing to challenge Decatur over a joking insult they overheard. Somers was wounded in the first two duels and had to be supported during the third (by Decatur, who was acting as his second).

Somers was detached from United States on June 13, 1801, and ordered to Boston on July 30, 1801. He served in the latter frigate in the Mediterranean. After Boston returned to Washington, DC, Somers was furloughed on November 11, 1802, to await orders.

First Barbary War
On May 5, 1803, Somers was ordered to Baltimore, Maryland, to man, fit out, and command USS Nautilus (1799), and when that schooner was ready for sea, to sail her to the Mediterranean. Nautilus got underway on 30 June, reached Gibraltar on July 27, and sailed four days later to Spain. He then returned to Gibraltar to meet Commodore Edward Preble, in Constitution, who was bringing a new squadron for action against the Barbary pirates. Nautilus sailed with Preble on October 6 to Tangier where the display of American naval strength induced the Europeans of Morocco to renew the treaty of 1786. Thereafter, Tripoli became the focus of Preble's attention.

Somers' service as commanding officer of Nautilus during operations against Tripoli won him promotion to master commandant on May 18, 1804. In the summer, he commanded a division of gunboats amidst five attacks on Tripoli, during the First Barbary War.

On September 4, 1804, Somers assumed command of the fire ship Intrepid, which had been fitted out as a "floating volcano", alongside 12 members of a volunteer crew. Intrepid was to be sailed into Tripoli harbor and blown up in the midst of the corsair fleet close under the walls of the city. That night, she got underway into the harbor, but she exploded prematurely, killing Somers and his entire crew.

Legacy
News of Somers' death would take some months to arrive to the United States, with newspapers in New York and New Jersey reporting on the assault in January 1805. Some reports suggested the premature detonation to be a deliberate act by Somers to avoid capture by approaching sailors, an account which led to Somers' depiction as a martyr within the American Navy. However, the true reasons for the explosion remain unclear and no reliable account is known from the Intrepid final moments.

Somers is buried in Tripoli, alongside the bodies of other sailors recovered from the explosion. In 2004, the New Jersey State Assembly passed two resolutions calling for the return of his remains. It was hoped that with the fall of Muammar Gaddafi's regime in Libya in August 2011 that the remains might finally be repatriated, but efforts by diplomatic staff and relatives of Somers in the United States remained unsuccessful as of 2015.

Since 1804, six ships of the US Navy have successively been named the USS Somers in his honor.

The town of Somers, New York, located in Westchester County is named in his honor. Somers Point, New Jersey, is named after Richard's great-grandfather. Every year there is a Richard Somers Day celebration in Somers Point.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Richard Somers


text:
USS Somers

USS Somers may refer to:

 * USS Somers (1812), was a schooner that fought on Lake Erie and Huron during the War of 1812. She was captured by the British in 1814.
 * USS Somers (1842), was a brig launched in 1842 and sunk in 1846. The ship is known for the Somers Affair.
 * USS Somers (TB-22), was a torpedo boat purchased in 1898 and sold in 1920
 * USS Somers (DD-301), was a Clemson-class destroyer launched in 1918, commissioned in 1920 and scrapped in 1931
 * USS Somers (DD-381), was a Somers-class destroyer launched, commissioned in 1937 and scrapped in 1947
 * USS Somers (DD-947), was a Forrest Sherman-class destroyer launched in 1958, commissioned in 1959 and sunk as target in 1998

title: USS Somers


text:
OS-9

OS-9 is a family of real-time, process-based, multitasking, multi-user operating systems, developed in the 1980s, originally by Microware Systems Corporation for the Motorola 6809 microprocessor. It was purchased by Radisys Corp in 2001, and was purchased again in 2013 by its current owner Microware LP.

The OS-9 family was popular for general-purpose computing and remains in use in commercial embedded systems and amongst hobbyists. Today, OS-9 is a product name used by both a Motorola 68000-series machine language OS and a portable (PowerPC, x86, ARM, MIPS, SH4, etc.) version written in C, originally known as OS-9000.

History
The first version ("OS-9 Level One"), which dates back to 1979–1980, was written in assembly language for the Motorola 6809 CPU, and all of its processes ran within the 64KB address space of the CPU without a memory management unit. It was developed as a supporting operating system for the BASIC09 project, contracted for by Motorola as part of the 6809 development. A later 6809 version ("Level Two") takes advantage of memory mapping hardware, supported up to 2 MB of memory (ca. 1980) in most implementations, and included a GUI on some platforms.

In 1983, OS-9/6809 was ported to Motorola 68000 assembly language and extended (called OS-9/68K); and a still later (1989) version was rewritten mostly in C for further portability. The portable version was initially called OS-9000 and was released for 80386 PC systems around 1989, then ported to PowerPC around 1995. These later versions lack the memory mapping facilities of OS-9/6809 Level Two simply because they do not need them. They used a single flat address space that all processes share; memory mapping hardware, if present, is mostly used to ensure that processes access only memory they have the right to access. The 680x0 and 80386 (and later) MPUs all directly support far more than 1 MB of memory in any case.

As a consequence of early pervasive design decisions taking advantage of the easily used reentrant object code capabilities of the 6809 processor, programs intended for OS-9 are required to be reentrant; compilers produce reentrant code automatically and assemblers for OS-9 offer considerable support for it. OS-9 also uses position-independent code and data because the 6809 also supports it directly; compilers and assemblers support position independence. The OS-9 kernel loads programs (including shared code), and allocates data, wherever sufficient free space is available in the memory map. This allows the entire OS and all applications to be placed in ROM or Flash memory, and eases memory management requirements when programs are loaded into RAM and run. Programs, device drivers, and I/O managers under OS-9 are all 'modules' and can be dynamically loaded and unloaded (subject to link counts) as needed.

OS-9/6809 runs on Motorola EXORbus systems using the Motorola 6809, SS-50 Bus and SS-50C bus systems from companies such as SWTPC, Tano, Gimix, Midwest Scientific, and Smoke Signal Broadcasting, STD-bus 6809 systems from several suppliers, personal computers such as the Fujitsu FM-11, FM-8, FM-7 and FM-77, Hitachi MB-S1, and many others.

System Industries, a third-party provider of DEC compatible equipment, used a 68B09E processor running OS9 in its QIC (quarter-inch cartridge) tape backup controllers in VAX installations.

The best known hardware (due to its low price and broad distribution) was the TRS-80 Color Computer (CoCo) and the similar Dragon series. Even on the CoCo, a quite minimalist hardware platform, it was possible under OS-9/6809 Level One to have more than one interactive user running concurrently (for example, one on the console keyboard, another in the background, and perhaps a third interactively via a serial connection) as well as several other non-interactive processes. One system, the Positron 9000, was positioned as a multi-user system for educational use, offering Microware's BASIC and Pascal environments, fitted with 64 KB to 512 KB of RAM, and featuring four to twelve serial ports. Responsiveness was reportedly impacted by multi-user operations in the system's minimal configuration, however. A second processor implementation of OS-9 for the BBC Micro was produced by Cumana. It included on-board RAM, SCSI hard disk interface and a MC68008 processor.

OS-9 was also ported to the Commodore SP-9000 or SuperPET, which had a 6809 in addition to the 6502 of the base 8032 model, as well as 64 KB more. The Toronto PET Users Group sponsored a HW/SW project which included a daughter board with an MMU as well as the OS-9 distribution disks. With two processors, 96 KB, a 25×80 screen and serial, parallel and IEEE-488 ports and many peripherals this was one of the most capable OS-9 systems available.

OS-9's multi-user and multi-tasking capabilities make it usable as a general-purpose interactive computer system. Many third-party interactive applications have been written for it, such as the Dynacalc spreadsheet, the VED text formatter, and the Stylograph and Screditor-3 WYSIWYG word processors. TSC's nroff emulating formatter was ported to OS-9 by MicroWay, as well.

In mid 1980s, OS-9 was selected for the CD-i operating system. Around the same time, Microsoft approached Microware for acquisition of the company primarily because it was attracted by CD-RTOS, the CD-i operating system. The negotiation failed and no deal was made; Microware decided to remain independent.

In late 1980s, Microware released OS-9000, a more portable version of the operating system. The vast majority of the operating system kernel was rewritten in C leaving a handful of hardware-dependent parts in assembly language. A few "more advanced features" were added such as tree-like kernel module name space. OS-9000 was initially ported to the Motorola 680x0 family CPUs, Intel 80386, and PowerPC. The OS-9000/680x0 was a marketing failure and withdrawn very quickly, probably because few customers wanted to try the fatter and slower operating system over the existing OS-9/680x0 proven record of stability. That the Motorola 680x0 family and VME board computer system vendors were nearing their end of life might have affected the unpopularity of OS-9000/680x0. Microware later started calling all of its operating systems — including what had been originally called OS-9000 — simply OS-9, and started shifting its business interest towards portable consumer device markets such as cellphones, car navigation, and multimedia.

In late 1980s and early 1990s, the Character Generators computers used in Broadcast Systems used OS-9 and OS-9000 extensively. The now defunct Pesa Electronica used OS-9 on their CGs such as CG 4722 and CG4733.

Name conflicts and court decisions
In 1999, nineteen years after the first release of OS-9, Apple Computer released Mac OS 9. Microware sued Apple that year for trademark infringement, although a judge ruled that there would be little chance for confusion between the two. Some Macintosh users who are unaware of Microware's lesser known OS-9 have posted to the comp.os.os9 newsgroup not realizing what OS-9 is.

In 2001, RadiSys purchased Microware to acquire the Intel IXP-1200 network processor resources. This acquisition infused Microware with capital and allowed Microware to continue OS-9 development and support.

On February 21, 2013, Microware LP (a partnership formed by Freestation of Japan, Microsys Electronics of Germany and RTSI LLC of the USA) announced that they signed an Asset Purchase Agreement to buy the rights to the names Microware, OS-9 and all assets from RadiSys.

Modern and archaic design
OS-9 (especially the 68k version and thereafter) clearly distinguishes itself from the prior generation of embedded operating systems in many aspects.
 * Runs on 8-bit, 16-bit, and 32-bit CPUs.
 * Clear separation between user mode and supervisor (kernel) mode.
 * Dynamic use of individually and separately built software components (executable program images and kernel modules) rather than a statically linked single monolithic image.
 * Unix-like process name-space model (not memory model) and user shell program.
 * Clear separation between hardware independent (e.g. file managers) and hardware dependent (e.g. device drivers) layers.

When compared with more modern operating systems:
 * The kernel is written entirely in assembly language (OS-9/68K version only) and C (portable version to other architectures) using simple internal data structures, reducing flexibility and improvement scope while improving determinability required for real-time operating systems.
 * Performance was also affected for some operations, but assembly language helped with the speed issue.
 * Systems without a memory management unit (MMU) have no memory protection against illegal access, nor per-process memory protection, while systems with an MMU can have memory protection enabled. The module controlling the MMU can be included or omitted by the system integrator to enable or disable memory protection. This allows OS-9 to run on older systems which do not include an MMU.
 * Older versions of OS-9 do not support POSIX threads, while all OS-9 supported processors support POSIX threads.
 * No SMP support for multiple sockets, cores, or hardware threads in the same OS-9 instance (can run as a RTOS on one of the cores of dual core processors like Core Duo and Core 2 Duo, when Linux is running on the other core doing general purpose tasks).

Task scheduling
OS-9's real-time kernel allows multiple independent applications to execute simultaneously through task switching and inter-process communication facilities. All OS-9 programs run as processes containing at least one lightweight process (thread) but may contain an effectively unlimited number of threads. Within a process, these lightweight processes share memory, I/O paths, and other resources in accordance with the POSIX threads specification and API. OS-9 schedules the threads using a fixed-priority preemptive scheduling algorithm with round-robin scheduling within each priority. Time slicing is supported. The priority levels can be divided into a range that supports aging and a higher-priority range that uses strict priority scheduling. Each process can access any system resource by issuing the appropriate OS-9 service request. At every scheduling point, OS-9 compares the priority of the thread at the head of the active queue to the priority of the current thread. It context switches to the thread on the active queue if its priority is higher than the current processes' priority. Aging artificially increases the effective priority of threads in the active queue as time passes. At defined intervals, time slicing returns the current thread to the active queue behind other threads at the same priority.

Kernel modules

 * Kernel – Contains task switching, memory allocation, and most non-I/O calls
 * IOMAN – Handles I/O calls to various file managers and drivers.
 * File managers basic set:
 * SCF, Serial files (serial devices)
 * RBF, Random block (disk devices)
 * SBF, Sequential block (tape Devices)
 * NFM, NULL devices (USB and other devices)
 * MFM, Message
 * PCF, PC FAT files
 * PIPEMAN, Pipe manager
 * Modman - Memory module directories
 * SSM – System security (MMU handling)
 * Cache – Cache handling,
 * VectXXX – Vector / PIC handler
 * FPU – Floating point emulation
 * Align – Address alignment fault handler

Commands
The following list of commands is supported by the OS-9 shell.

Shell built-in commands

 * chd
 * chx
 * kill
 * w
 * wait
 * setenv
 * unsetenv
 * setpr
 * logout
 * profile
 * ex
 * -e
 * -ne
 * -p
 * -p=
 * -np
 * -t
 * -nt
 * -v
 * -nv
 * -x
 * -nx

Utilities for operating system functions

 * attr
 * copy
 * date
 * deiniz
 * del
 * deldir
 * dsave
 * dump
 * echo
 * fixmod
 * free
 * ident
 * iniz
 * link
 * list
 * load
 * makdir
 * mdir
 * merge
 * mfree
 * pd
 * pr
 * printenv
 * procs
 * rename
 * save
 * shell
 * setime
 * sleep
 * tee
 * tmode
 * touch
 * unlink

System management utilities

 * backup
 * dcheck
 * devs
 * format
 * frestore
 * fsave
 * irqs
 * login
 * os9gen
 * tsmon
 * xmode

General utilities

 * binex
 * build
 * cfp
 * cmp
 * code
 * compress
 * count
 * edt
 * exbin
 * expand
 * grep
 * help
 * make
 * qsort
 * tr
 * umacs

Comparisons with Unix
OS-9's notion of processes and I/O paths is quite similar to that of Unix in nearly all respects, but there are some significant differences. Firstly, the file system is not a single tree, but instead is a forest with each tree corresponding to a device. Second, OS-9 does not have a Unix-style fork system call—instead it has a system call which creates a process running a specified program, performing much the same function as a fork-exec or a spawn. Additionally, OS-9 processes keep track of two "current directories" rather than just one; the "current execution directory" is where it will by default look first to load programs to run (which is similar to the use of PATH environment variable under UNIX). The other is the current data directory.

Another difference is that in OS-9, grandparent directories can be indicated by repeating periods three or more times, without any intervening slashes (a feature also found in 4DOS/4OS2/4NT/TC). For example,  in OS-9, is similar to   in Unix. But  and , with just one or two periods, each work the same in both OS-9 and Unix.

OS-9 has had a modular design from the beginning, influenced by notions of the designers of the 6809 and how they expected software would be distributed in the future (see the three-part series of articles in January-March 1979 Byte by Terry Ritter, et al. of Motorola who designed the CPU).

The module structure requires more explanation: OS-9 keeps a "module directory", a memory-resident list of all modules that are in memory either by having been loaded, or by having been found in ROM during an initial scan at boot time. When one types a command to the OS-9 shell, it will look first in the current module directory for a module of the specified name and will use it (and increase its link count) if found, or it will look on disk for an appropriately named file if not. In OS-9/6809 and OS-9/68000, the module directory is flat, but OS-9000 made the module directory tree-structured. The OS-9000 shell looks in one's alternative module directory for a MODPATH environment variable, analogous to the PATH variable in all versions, indicating the sequence of module directories in which to look for pre-loaded modules.

Modules are not only used to hold programs, but can also be created on the fly to hold data, and are the way in which OS-9 supports shared memory. OS-9/non-68000 supports POSIX threads. A single process can start any number of threads.

Status
OS-9 has faded from popular use, though Microware LP does still support it and it does run on modern architectures such as ARM and x86. The compiler provided, Ultra C/C++, supports C89, but supports neither C99 nor C++98. Ultra C++ does provide limited support for C++ templates. It is also supported by popular SSL/TLS libraries such as wolfSSL.
 * A Version of OS-9 running Steve Adams' G-Windows is present on semiconductor wafer scrubbers manufactured by Ontrak Systems / Lam Research. Thousands of these systems are in use today, however, the software running on them dates to 1999 when the last version was created to handle Y2K issues.
 * Versions of OS-9/68K ran on a wide variety of 68000 family platforms, including the X68000 in Japan, some personal computers intended by their designers as upgrades from the Color Computer (e.g., the 68070 and 68340-based MM/1, and on other computers from Frank Hogg Laboratories, PEP Modular Computers, and Delmar Co.) It was also ported to the Atari ST by Recc-o-ware in the early 1990s, and was distributed by Cumana in Europe. A port for 68000-based Apple Macintoshes distributed by Ultrascience exists. A port to the Amiga by Digby Tarvin is also purported to exist.
 * OS-9/68K is mandated by Caltrans to be used in the 2070-1B and 2070-1E controller cards, and so ends up being used to run many North American traffic signal control systems.
 * OS-9/68K is also found in some other embedded applications, including the Quanta Delta television broadcast character generator, still in production by ScanLine Technologies in Utah. While the user-level interface code on this system started at boot time, there was a hidden, undocumented keyboard sequence that would provide a user with a root shell prompt in a scroll window on the device's edit-channel monitor.
 * In the embedded market, where OS-9 has found application in such devices as the Fairlight CMI synthesizers, robotics, in-car navigation systems, and Philips' Compact Disc-Interactive (CD-i) industry standard.
 * The TRS-80 Color Computer (and clones) still has users and an annual conference in Chicago; as of 2018 the 27th Annual "Last" Chicago CoCoFEST was scheduled for April 21-22, 2018. A group of Canadian programmers rewrote OS-9/6809 Level II for the CoCo 3 (w/ address translation hardware) for efficiency, and to take advantage of the native mode of the Hitachi 6309. Today's serious CoCo users now typically have replaced the 68B09E in the CoCo 3 with an Hitachi 63B09E and run the rewrite, called NitrOS-9. The combination is surprisingly fast, considering that it runs on an expressly low cost, 8-bit computer system.
 * Gary Becker's CoCo3 FPGA is a synthesized TRS-80 Color Computer which runs NitrOS-9 on an Altera DE-1 development board. The core 6809 CPU was designed by John Kent and is currently running at 25 MHz.
 * OS-9000/80x86 can be run on PC-type machines built around the Intel x86 CPUs. OS-9000 has also been ported to the PowerPC, MIPS, some versions of Advanced RISC Machines' ARM processor, and some of the Hitachi SH family of processors.
 * The DigiCart/II Plus audio playback unit runs OS-9/68K. It is a solid state replacement for radio station style cart players. These units are used in radio and at places like Walt Disney World where they play park announcements.
 * German electronics manufacturer Eltec has been manufacturing the Eurocom-model CPU boards for industrial purposes since the late 1970s, starting with the 6802 and 6809 Eurocom-1 and Eurocom-2, and onwards with 68K, and derivative, CPU boards up to today. The modern boards can be delivered with a range of operating systems, amongst which is OS-9.
 * Omron used OS-9 in their NS series HMI panels. However, for their new NA series, Omron selected Windows Embedded Compact 7. Omron indicated that with OS-9 nearly all the drivers, for example for a USB stick, had to be written by Omron.
 * OS-9000/SH4 can be found in loader (inside KIWI-format container LOADING.KWI) on Map CD/DVD for old automotive GPS navigation systems made by Matsushita for Japan domestical market.

title: OS-9


text:
Extension (metaphysics)

In metaphysics, extension signifies both 'stretching out' (Latin: extensio) as well as later 'taking up space', and most recently, spreading one's internal mental cognition into the external world.

The history of thinking about extension can be traced back at least to Archytas' spear analogy for the infinity of space. How far can one's hand or spear stretch out until it reaches the edge of reality? "If I arrived at the outermost edge of the heaven, could I extend my hand or staff into what is outside or not? It would be paradoxical [given our normal assumptions about the nature of space] not to be able to extend it."

Descartes
René Descartes defined extension as the property of existing in more than one dimension, a property that was later followed up in Grassmann's n-dimensional algebra. For Descartes, the primary characteristic of matter is extension (res extensa), just as the primary characteristic of mind is thought (res cogitans).

Newton
After rejecting Cartesian identification of body with extension, Newton turns to the question of what the nature of the "immobile being"—space or extension itself, distinguished from body—was. He raises three possible definitions for extension: as a kind of substance; or as a kind of accident (a standard philosophical term for attribute: anything that can be predicated of substance); or "simply nothing" (a reference to atomism), all of which he repudiates. Instead he proposes that extension "has a certain mode of existence of its own, which agrees neither with substances nor accidents." After struggling with this question, Newton provides perhaps one of the clearest definitions of extension

"If we say with Descartes that extension is body, do we not manifestly offer a path to Atheism, both because extension is not a creature but has existed eternally, and because we have an absolute Idea of it without any relationship to God, and therefore we are able to conceive of it as existent while feigning the non-existence of God?"

which lead Stein to conclude Newton's conception of Space, the existence of space, or extension, follows from that of anything whatsoever; but extension does not require a subject in which it "inheres", as a property; and it can be conceived as existent without presupposing any particular thing, God included. On the other hand, it is an "affection of every being."

Locke
John Locke, in An Essay Concerning Human Understanding, defined extension as "only the Space that lies between the Extremities of those solid coherent Parts" of a body. It is the space possessed by a body. Locke refers to the extension in conjunction with solidity and impenetrability, the other primary characteristics of matter.

Spinoza
Extension also plays an important part in the philosophy of Baruch Spinoza, who says that substance (that which has extension) can be limited only by substance of the same sort, i.e. matter cannot be limited by ideas and vice versa. From this principle, he determines that substance is infinite. This infinite substance is what Spinoza calls God, or better yet nature, and it possesses both unlimited extension and unlimited consciousness.

Infinite divisibility
Infinite divisibility refers to the idea that extension, or quantity, when divided and further divided infinitely, cannot reach the point of zero quantity. It can be divided into very small or negligible quantity but not zero or no quantity at all. Using a mathematical approach, specifically geometric models, Gottfried Leibniz and Descartes discussed the infinite divisibility of extension. Actual divisibility may be limited due to unavailability of cutting instruments, but its possibility of breaking into smaller pieces is infinite.

Compenetration
Compenetration refers to two or more extensions occupying the same space at the same time. This, according to scholastic philosophers, is impossible; according to this view, only spirits or spiritualized matter can occupy a place occupied already by an entity (matter or spirit)

Extended mind thesis
In more recent work, philosophers David Chalmers and Andy Clark in 1998 published "The Extended Mind." This has opened a wide channel of new research at the nexus of epistemology, philosophy of mind, cognitive and neuro-science, dynamic systems thinking, science, technology & innovation studies.

title: Extension (metaphysics)


text:
Extension (semantics)

In any of several fields of study that treat the use of signs — for example, in linguistics, logic, mathematics, semantics, semiotics, and philosophy of language — the extension of a concept, idea, or sign consists of the things to which it applies, in contrast with its comprehension or intension, which consists very roughly of the ideas, properties, or corresponding signs that are implied or suggested by the concept in question.

In philosophical semantics or the philosophy of language, the 'extension' of a concept or expression is the set of things it extends to, or applies to, if it is the sort of concept or expression that a single object by itself can satisfy. Concepts and expressions of this sort are monadic or "one-place" concepts and expressions.

So the extension of the word "dog" is the set of all (past, present and future) dogs in the world: the set includes Fido, Rover, Lassie, Rex, and so on. The extension of the phrase "Wikipedia reader" includes each person who has ever read Wikipedia, including you.

The extension of a whole statement, as opposed to a word or phrase, is defined (since Gottlob Frege's "On Sense and Reference") as its truth value. So the extension of "Lassie is famous" is the logical value 'true', since Lassie is famous.

Some concepts and expressions are such that they don't apply to objects individually, but rather serve to relate objects to objects. For example, the words "before" and "after" do not apply to objects individually—it makes no sense to say "Jim is before" or "Jim is after"—but to one thing in relation to another, as in "The wedding is before the reception" and "The reception is after the wedding". Such "relational" or "polyadic" ("many-place") concepts and expressions have, for their extension, the set of all sequences of objects that satisfy the concept or expression in question. So the extension of "before" is the set of all (ordered) pairs of objects such that the first one is before the second one.

Mathematics
In mathematics, the 'extension' of a mathematical concept $$C$$ is the set that is specified by $$C$$. (That set might be empty, currently.)

For example, the extension of a function is a set of ordered pairs that pair up the arguments and values of the function; in other words, the function's graph. The extension of an object in abstract algebra, such as a group, is the underlying set of the object. The extension of a set is the set itself. That a set can capture the notion of the extension of anything is the idea behind the axiom of extensionality in axiomatic set theory.

This kind of extension is used so constantly in contemporary mathematics based on set theory that it can be called an implicit assumption. A typical effort in mathematics evolves out of an observed mathematical object requiring description, the challenge being to find a characterization for which the object becomes the extension.

Computer science
In computer science, some database textbooks use the term 'intension' to refer to the schema of a database, and 'extension' to refer to particular instances of a database.

Metaphysical implications
There is an ongoing controversy in metaphysics about whether or not there are, in addition to actual, existing things, non-actual or nonexistent things. If there are—if, for instance, there are possible but non-actual dogs (dogs of some non-actual but possible species, perhaps) or nonexistent beings (like Sherlock Holmes, perhaps)—then these things might also figure in the extensions of various concepts and expressions. If not, only existing, actual things can be in the extension of a concept or expression. Note that "actual" may not mean the same as "existing". Perhaps there exist things that are merely possible, but not actual. (Maybe they exist in other universes, and these universes are other "possible worlds"—possible alternatives to the actual world.) Perhaps some actual things are nonexistent. (Sherlock Holmes seems to be an actual example of a fictional character; one might think there are many other characters Arthur Conan Doyle might have invented, though he actually invented Holmes.)

A similar problem arises for objects that no longer exist. The extension of the term "Socrates", for example, seems to be a (currently) non-existent object. Free logic is one attempt to avoid some of these problems.

General semantics
Some fundamental formulations in the field of general semantics rely heavily on a valuation of extension over intension. See for example extension, and the extensional devices.

title: Extension (semantics)


text:
Mary Martin

Mary Virginia Martin (December 1, 1913 – November 3, 1990) was an American actress and singer. A muse of Rodgers and Hammerstein, she originated many leading roles on stage over her career, including Nellie Forbush in South Pacific (1949), the title character in Peter Pan (1954), and Maria von Trapp in The Sound of Music (1959). She was named a Kennedy Center Honoree in 1989. She was the mother of actor Larry Hagman.

Early life
Martin was born in Weatherford, Texas. Her autobiography described her childhood as secure and happy. She had close relationships with both of her parents as well as her siblings. As a young actress Martin had an instinctive ear for recreating musical sounds.

Martin's father, Preston Martin, was a lawyer, and her mother, Juanita Presley, was a violin teacher. Although the doctors told Juanita that she would risk her life if she attempted to have another baby, she was determined to have a boy. Instead, she had Mary, who became a tomboy.

Martin's family had a barn and orchard that kept her entertained. She played with her elder sister Geraldine (whom she called "Sister"), climbing trees and riding ponies. Martin adored her father. "He was tall, good-looking, silver-haired, with the kindest brown eyes. Mother was the disciplinarian, but it was Daddy who could turn me into an angel with just one look." Martin, who said "I'd never understand the law" began singing at a bandstand, outside the courtroom where her father worked every Saturday night. She sang in a trio with her sister and Marion Swofford, all three in bellhop costumes. "Even in those days, without microphones, my high piping voice carried all over the square. I have always thought that I inherited my carrying voice from my father."

She remembered having a photographic memory as a child. School tests were not a problem, and learning songs was easy. She had her first experience of singing solo at a fire hall, where she felt the crowd's appreciation. "Sometimes I think that I cheated my own family and my closest friends by giving to audiences so much of the love I might have kept for them. But that's the way I was made; I truly don't think I could help it." Martin's craft was developed by seeing movies and becoming a mimic. She would win prizes for looking, acting and dancing like Ruby Keeler and singing exactly like Bing Crosby. "Never, never, never can I say I had a frustrating childhood. It was all joy. Mother used to say she never had seen such a happy child — that I awakened each morning with a smile. I don't remember that, but I do remember that I never wanted to go to bed, to go to sleep, for fear I'd miss something."

Marriage
During high school, Martin dated Benjamin Hagman before she left to attend finishing school at Ward–Belmont in Nashville, Tennessee. In Nashville she enjoyed imitating Fanny Brice at singing gigs, but she found school dull and felt confined by its strict rules. She was homesick for Weatherford, her family and Hagman. During a visit, Mary and Benjamin persuaded Mary's mother to allow them to marry. She was legally married on November 3, 1930, at Grace Episcopal Church (Hopkinsville, Kentucky). 10 months later, pregnant with her first child (Larry Hagman) she was forced to leave Ward–Belmont. She was, however, happy to begin her new life, but she soon learned that this life as she would later say was nothing but "role playing".

Their honeymoon was at her parents' house, and Martin's dream of life with a family and a white-picket fence faded. "I was 17, a married woman without real responsibilities, miserable about my mixed-up emotions, afraid there was something awfully wrong with me because I didn't enjoy being a wife. Worst of all, I didn't have enough to do." (p. 39) It was "Sister" who came to her rescue, suggesting that she should teach dance. "Sister" taught Martin her first real dance—the waltz clog. Martin perfectly imitated her first dance move, and she opened a dance studio. Here, she created her own moves, imitated the famous dancers she watched in the movies and taught "Sister's" waltz clog. As she later recalled, "I was doing something I wanted to do—creating."

Apprenticeship
Wanting to learn more moves, Martin went to California to attend the dance school at the Franchon and Marco School of the Theatre and then opened her own dance studio in Mineral Wells, Texas. She was given a ballroom studio with the premise that she would sing in the lobby every Saturday. There, she learned how to sing into a microphone and how to phrase blues songs. One day at work, she accidentally walked into the wrong room, where auditions were being held. They asked her in what key she would like to sing "How Red the Rose, How Blue the Sky". Having absolutely no idea what her key was, she sang regardless and got the job.

Returning to California, Martin was hired to sing "How Red the Rose" at the Fox Theater in San Francisco followed by a gig at the Paramount Theater in Los Angeles. There was one catch: she had to sing in the wings. She scored her first professional gig unaware that she would soon be center stage.

Soon after, Martin learned that her studio in Texas had been burned down by a man who thought dancing was a sin. She began to express her unhappiness. Her father gave her advice, saying she was too young to be married. Martin left everything behind including her young son, Larry, and stayed in Los Angeles while her father handled her divorce from Benjamin Hagman for her. In Los Angeles, Martin plunged herself into auditions—so many that she became known as "Audition Mary". Her first professional audition and job was on a national radio network. Among Martin's first auditions, she sang "Indian Love Call". After she finished the song, "a tall, craggly man who looked like a mountain" told Martin that he thought she had something special. It was Oscar Hammerstein II This marked the start of her career.

Radio
Martin began her radio career in 1939 as the vocalist on a short-lived revival of The Tuesday Night Party on CBS. In 1940, she was a singer on NBC's Good News of 1940, which was renamed Maxwell House Coffee Time during that year. In 1942, she joined the cast of Kraft Music Hall on NBC, replacing Connie Boswell. She was also one of the stars of Stage Door Canteen on CBS, 1942–1945.

Broadway

Martin was cast in Cole Porter's Leave It to Me!, making her Broadway debut in November 1938 in that production. She became popular on Broadway and received attention in the national media singing the spoof striptease song "My Heart Belongs to Daddy". With that one song in the second act, she became a star 'overnight'. Martin reprised the song in Night and Day, a Hollywood film about Cole Porter, in which she played herself auditioning for Porter (Cary Grant). "My Heart Belongs to Daddy" catapulted her career and became very special to Martin—she even sang it to her ailing father in his hospital bed while he was in a coma. Martin did not learn immediately that her father had died. Headlines read "Daddy Girl Sings About Daddy as Daddy Dies". Because of the show's demanding schedule, Martin was unable to attend her father's funeral. In 1943 she starred in the new Kurt Weill musical One Touch of Venus and then Lute Song in 1946.

As nurse Nellie Forbush, Martin opened on Broadway in South Pacific on April 7, 1949. Her performance was called "memorable ... funny and poignant in turns", and she earned a Tony Award. Richard Watts Jr. of the New York Post wrote: "nothing I have ever seen her do prepared me for the loveliness, humor, gift for joyous characterization, and sheer lovableness of her portrayal of Nellie Forbush .... Hers is a completely irresistible performance." She opened in the West End production on November 1, 1951.

Her next major success was in the role of Peter in the Broadway production of Peter Pan in October 1954 with Martin winning the Tony Award.

Martin opened on Broadway in The Sound of Music as Maria on November 16, 1959, and stayed in the show until October 1961. She won the Tony Award for Best Actress in a Musical. The musical gave Martin "the chance to display her homespun charm".

In 1966, she appeared on Broadway in the two-person musical I Do! I Do! with Robert Preston and was nominated for the Tony Award (Leading Actress in a Musical). A national tour with Preston began in March 1968 but was canceled early due to Martin's illness.

Although she appeared in nine films between 1938 and 1943, she was generally passed over for the filmed version of the musical plays. She herself once explained that she did not enjoy making films because she did not have the connection with an audience that she had in live performances. The closest that she ever came to preserving her stage performances was her television appearances as Peter Pan. The Broadway production from 1954 was subsequently performed on NBC television in RCA's compatible color in 1955, 1956, and 1960. Martin also preserved her 1957 stage performance as Annie Oakley in Annie Get Your Gun when NBC television broadcast the production live that year.

While Martin did not enjoy making films, she frequently appeared on television. Her last feature film appearance was a cameo as herself in MGM's Main Street to Broadway in 1953. Martin made an appearance in 1980 in a Royal Variety Performance in London performing "Honeybun" from South Pacific. Martin appeared in the play Legends with Carol Channing in a one-year US national tour opening in Dallas on January 9, 1986.

Awards and honors
Martin was inducted into the American Theater Hall of Fame in 1973. She received the Kennedy Center Honors, an annual honor for career achievements, in 1989. She received the Donaldson Award in 1943 for One Touch of Venus. A Special Tony Award was presented to her in 1948 while she appeared in the national touring company of Annie Get Your Gun for "spreading theatre to the rest of the country while the originals perform in New York." In 1955 and 1956, she received, first, a Tony Award for Peter Pan, and then an Emmy for appearing in the same role on television. She also received Tonys for South Pacific and in 1959 for The Sound of Music.

In September 1963, a statue of Peter Pan dedicated to her was unveiled in Weatherford, donated by the Peter Pan Peanut Butter Company.

Personal life
After Martin's 1936 divorce from Benjamin Hagman, she married Richard Halliday in 1940. Early in their marriage, he worked as a drama critic for the New York World-Telegram and a movie critic for the New York Daily News. Eventually, Halliday became producer or co-producer of at least two of Martin's projects. In the early 1970s, the couple lived, according to his March 1973 obituary in the Connecticut Sunday Herald, "on a vast ranch they own near Anápolis" in the state of Goiás, Brazil. The ranch was called "Nossa Fazenda Halliday" (Our Halliday Farm). Martin was called Dona Maria by people in the vicinity of the Brazilian ranch.

Cultural scholar Lillian Faderman wrote that Martin and actress Janet Gaynor often traveled together along with Halliday and with Gaynor's husband.

Gaynor and her husband discovered Anápolis in 1950, soon after, Martin and her husband visited. Martin and Janet Gaynor had adjoining ranches near Anápolis, Goiás, Brazil.

On the evening of September 5, 1982, Martin, Janet Gaynor, Gaynor's husband Paul Gregory, and Martin's manager Ben Washer were involved in a serious car crash in San Francisco. A van ran a red light at the corner of California and Franklin streets and crashed into the Luxor taxicab in which the group was riding, knocking it into a tree. Washer was killed, Martin sustained two broken ribs and a broken pelvis, and Gaynor's husband suffered two broken legs. Gaynor sustained several serious injuries. The driver of the van was arrested on two counts of felony drunk driving, reckless driving, speeding, running a red light, and vehicular homicide. On March 15, 1983, he was found guilty of drunk driving and vehicular homicide and was sentenced to three years in prison. Gaynor died two years later from complications from her injuries.

Martin was a Democrat and supported Adlai Stevenson during the 1952 presidential election.

Martin's sexuality has long been a topic of debate. In 1979, Patsy Kelly told Boze Hadleigh that Martin was a lesbian. In 2016, biographer David Kaufman stated that Halliday served as "[Martin's] husband, her best friend, her gay/straight 'cover,'" while in 2019, The Advocate stated that Martin "simply [was the subject of] a lifetime of lavender rumors."

Death

Martin died of cancer at age 76 at her home in Rancho Mirage, California, on November 3, 1990. She is buried in City Greenwood Cemetery in Weatherford, Texas.

title: Mary Martin