Diogo de Carvalho e Sampayo (28 May 1750 – 29 December 1807) was a Portuguese nobleman, magistrate, diplomat and scientist. A knight of the

Order of Malta The Sovereign Military Order of Malta (SMOM), officially the Sovereign Military Hospitaller Order of Saint John of Jerusalem, of Rhodes and of Malta ( it, Sovrano Militare Ordine Ospedaliero di San Giovanni di Gerusalemme, di Rodi e di Malta; ...

and a judge by profession, Carvalho e Sampayo became notable as an amateur scientist who authored two important works on the subject of chromatics.

Biography

Carvalho e Sampayo was born in the Casa do Poço, a manor house in the city of

Lamego Lamego (; cel-x-proto, Lamecum) is a city and municipality in the Viseu District, in the Norte Region, Portugal, Norte Region of the Douro Subregion, Douro in northern Portugal. Located on the shores of the Balsemão River, the municipality has a ...

Portugal Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwestern Europe, and whose territory also includes the Atlantic archipelagos of ...

, to Diogo Lopes de Carvalho and Catarina Teresa de Vasconcelos, of a prominent gentry family. He graduated from the

University of Coimbra The University of Coimbra (UC; pt, Universidade de Coimbra, ) is a Public university, public research university in Coimbra, Portugal. First established in Lisbon in 1290, it went through a number of relocations until moving permanently to Coi ...

where he studied Law, later, in 1783, serving as a judge in

Viana do Castelo Viana do Castelo () is a municipality and seat of the district of Viana do Castelo in the Norte Region of Portugal. The population in 2011 was 88,725, in an area of 319.02 km². The urbanized area of the municipality, comprising the city, ...

. He resigned from his post after a conflict with the administrative authorities of the nearby town of Vila do Conde. At age 35, he joined the

, and it was around this time, during his stay in Malta, that he started working on colour problems and ended up writing two books on the subject in rapid succession: the first was published in 1787, under the title ''Tratado das Cores'' ("A Treatise on Colours"); the second, in 1788, was titled ''Dissertação sobre as Cores Primitivas'' ("A Dissertation on Primitive Colours"). Linear colour scales, Sampayo 1788

Sampayo devised a system of six simple colours (white, black, yellow, red, blue, and green), which he called ''generic colours'', and combined each colour with the other five colours in turn, each combination having three intermediate grades, resulting in four steps: this would generate 15 linear scales. Sampayo's system is the first fully coloured system of one-dimensional simple hue and tint/shade scales as well as a gray scale.

Johann Wolfgang von Goethe Johann Wolfgang von Goethe (28 August 1749 – 22 March 1832) was a German poet, playwright, novelist, scientist, statesman, theatre director, and critic. His works include plays, poetry, literature, and aesthetic criticism, as well as trea ...

was familiar with Carvalho e Sampayo's work: his seminal treatise ''

Theory of Colours ''Theory of Colours'' (german: Zur Farbenlehre, links=no) is a book by Johann Wolfgang von Goethe about the poet's views on the nature of colours and how these are perceived by humans. It was published in German in 1810 and in English in 1840. ...

'' (published 1810) includes a general assessment of Sampayo's 1791 book ''Memória sobre a Formação Natural das Cores'' ("An Essay on the Natural Formation of Colours"). Starting in 1789, he moved to

Madrid Madrid ( , ) is the capital and most populous city of Spain. The city has almost 3.4 million inhabitants and a metropolitan area population of approximately 6.7 million. It is the second-largest city in the European Union (EU), and ...

where he headed the Portuguese diplomatic representation there, first as ''

chargé d'affaires A ''chargé d'affaires'' (), plural ''chargés d'affaires'', often shortened to ''chargé'' (French) and sometimes in colloquial English to ''charge-D'', is a diplomat who serves as an embassy's chief of mission in the absence of the ambassador ...

'', then as a minister plenipotentiary, and finally as

ambassador extraordinary An ambassador is an official envoy, especially a high-ranking diplomat who represents a state and is usually accredited to another sovereign state or to an international organization as the resident representative of their own government or sov ...

, returning definitely to Portugal in 1801. In Madrid, Carvalho e Sampayo made acquaintance with

Wilhelm von Humboldt Friedrich Wilhelm Christian Karl Ferdinand von Humboldt (, also , ; ; 22 June 1767 – 8 April 1835) was a Prussian philosopher, linguist, government functionary, diplomat, and founder of the Humboldt University of Berlin, which was named after ...

References

{{DEFAULTSORT:Carvalho e Sampayo, Diogo de 1750 births 1807 deaths Color scientists People from Lamego Portuguese diplomats 18th-century Portuguese judges University of Coimbra alumni