Restoro d'Arezzo

Background

Restoro d'Arezzo was born around 1210-1220 in Arezzo, Italy.

Career

The scanty information available on Ristoro’s life derives entirely from his Composizione del mondo, which he completed in Arezzo in 1282. The work is in the vernacular and is thus the oldest surviving scientific text in Italian. Ristoro mentions that he wrote his treatise in a monastery, which suggests that he was a monk, but of which order is not known.

Convinced that “it is a dreadful thing for the inhabitant of a house not to know how it is made,” Ristoro collected in the Composizione del mondo all available knowledge of cosmology. The work begins with a detailed treatment of astronomy and astrology; he made no distinction between them. He described, in particular, the eight heavens of the fixed stars and the known planets and the four spheres corresponding to the four elements. For Ristoro the importance of the celestial bodies lay in their influence upon the earth, and he likened the action of the stars on terrestrial phenomena to that of a seal that gives form and nobility to wax, itself a shapeless and vulgar material. Every known celestial and terrestrial phenomenon was described by Ristoro, from the distribution of earth and seas, to the creation and disintegration of mountains, from meteorology to the circulation of waters, from plants and animals to the consideration of man, “the most noble of all the animals.”

Ristoro’s work was essentially a compilation from ancient authors, available to him either in the original, like Aristotle’s De coelo, or through Arabic translations and adaptations that were subsequently rendered into Latin, such as the Liber de aggregationibus, stellarum of al-Farghānī. The compilation, however, contains some startling critical comments: for instance, he denied that the motion of the spheres caused heavenly music; and he attributed the twinkling of the stars to the eye, rather than to the stars themselves. There are also noteworthy personal observations, including the description of the total solar eclipse that he observed in Arezzo in 1239. “The sky was clear and without clouds when the air began to turn yellow, and I saw the body of the sun being covered little by little until it became obscured and it was night; and I saw Mercury near the sun, and all the stars could be seen…. All the animals and the birds became frightened, and the wild beasts could be captured with ease…. And I saw the sun remain covered the length of time a man can walk 250 paces, and the air and the earth began to grow cold.”

Of considerable interest are observations that Ristoro made on the natural history of the regions surrounding Arezzo and Siena. While traveling through the marine Pliocene terrains of those regions, he recognized the organic nature of the fossil remains and the great variety of their shapes and attributed their presence in the hills to the universal deluge.

He made other observations on the calcareous encrusting power of certain hydrothermal springs and on emanations of natural gas. In a passage that is fairly representative of his thought, Ristoro points out that both natural and human environments must change with time, even though he was mistaken in considering the two kinds of phenomena on the same level and in taking as his example an unrealistically brief period.

Achievements

• Ristoro’s most known work is titled Composizione del mondo, which was considered as the most complete knowledge of cosmology at his time. The work begins with a detailed treatment of astronomy and astrology where he gave a description of the eight heavens of the fixed stars and the known planets and the four spheres corresponding to the four elements. Every known celestial and terrestrial phenomenon was described by Ristoro, from the distribution of earth and seas, to the creation and disintegration of mountains.
  
  Another Ristoro’s achievement was in his work making a compilation of knowledge that remained available from ancient authors, which he studied either in the original, like Aristotle’s De coelo, or through Arabic translations and adaptations that were subsequently rendered into Latin, such as the Liber de aggregationibus, stellarum of al-Farghānī. He also left some noteworthy personal observations, including the description of the total solar eclipse that he observed in Arezzo in 1239.
  
  Also, as a remarkable natural historian, Ristoro made some valuable observations on the calcareous encrusting power of certain hydrothermal springs and on emanations of natural gas, as well as on the natural history of the regions surrounding Arezzo and Siena.
  
  

Works

More photos

• book

  • Della composizione del mondo di Ristoro d'Arezzo testo italiano del 1282 già pubblicato da Enrico Narducci ed ora in più comoda forma ridotto 1282
  • La Composizione Del Mondo 1282

Views

Opinions on Ristoro’s position in the history of the sciences are divided; some consider him to be a mere medieval compiler, his ideas dominated by Aristotelian and Scholastic conceptions of the world; others, emphasizing his keen powers of observation, see him as a direct precursor of the Renaissance.

In fact, Ristoro was in every way a child of his times, even if he was a scholar of great intelligence and wide knowledge. Although he insisted that his observations of nature were made personally and in specific places, he names none of the places in question; much of the work of his commentators has thus become a task of identification.

Observations of nature rapidly acquired in his mind an abstract character and were not regarded as meaningless when detached from reality. The general tenet of recent historical criticism can well be applied to Ristoro: medieval artists and writers had a keen sense of observation, but their contact with the reality of the senses was limited to the specific and the episodic. Hence their depiction of particular details was realistic, but their conception of the whole was not, a generalization of which the Composizione del mondo provides a perfect example.

Quotations: "If a man returned to his region after less than a thousand years, he would not recognize the places he had known, because he would find the mountains worn down and changed, and in like manner the valleys, streams, rivers, springs, cities, hamlets and villages, and even the language. Where he had left a city, he would find woods, and vice versa; where a mountain had stood, a valley would now be and vice versa; and he would find his region everywhere deeply changed so that it would never seem to him that he had been there before."

Personality

D'Arezzo's interest in the science of the stars was paramount, but he was also an artist, skilled in drawing, painting, and illuminating. An indication of his refined artistic taste and of his keen spirit of observation is his description of the decorative patterns of a number of Etruscan and Roman vases (arretina vasa), in which he admired, besides other features, the fine representation of plants, animals, mountains, valleys, rivers, and forests. His critical judgment is all the more striking in a time when archaeological remains were poorly understood and ignored.

Interests

• drawing, painting

References

• Dictionary of Scientific Biography Volume 11
  1975
• Accredited citations in Ristoro d'Arezzo's Composizione del mondo: a study of sources
  1913