4 ms·

Gregorian calendar was directly adopted in many places. It is still Gregorian calendar in France as is Ming vase sitting in a museum in New York. Arabic numeral

Gregorian calendar was directly adopted in many places. It is still Gregorian calendar in France as is Ming vase sitting in a museum in New York. Arabic numerals used on Space Station do not stop being arabic just because there is no Arab in sight.

mc32 5y ago
The numerals are "Indo-Arabic". Arabs were a conduit but the number system was invented in the Indian subcontinent by Indian mathematicians, this was then adopted, centuries later, by Arab mathematicians who in turn exported/exposed it to the West.
- lmilcin 5y ago
  It is arabic numerals (https://en.wikipedia.org/wiki/Arabic_numerals https://en.wikipedia.org/wiki/Arabic_numerals). "Although the Hindu–Arabic numeral system[1][2] (i.e. decimal) was developed by Indian mathematicians around AD 500,[3] quite different forms for the digits were used initially. They were modified into Arabic numerals later in North Africa. " Arabic numerals does not only describe the concept of decimal system, but also the shape of digits. Hence "arabic numerals" is the correct description, and "Hindu-Arabic numerals" describes different numerals -- shapes for digits.
  - mc32 5y ago
    Fair enough. The numeral system is Hindu and the typography is derived from Arabic thus Arabic, although what we use in most of the rest of the world diverges quite a bit from truly Arabic typographs. One could argue 0, 1, 2, 3, 9 are similar with some rotation , but 4, 5, 6, 7, and 8 do not look like Arabic numbers. Curiously there is overlap of some E. Arabic numerals and Brahmi numerals.
  - jhgb 5y ago
    I'd definitely go with Chrisomalis on this one and just call them "Western numerals" to distinguish them from both Western Arabic and Eastern Arabic numerals. As you say, it's about the different shapes, and the three are definitely not the same.
- kragen 5y ago
  The numbering system was invented in India, but the particular numerals used for it in Europe (012345689) were invented by Arabs in North Africa. All the Europeans did with them was to rotate the "4" by 90°. This is easy to get confused about because of the subsequent conquest of North Africa by Europeans and the divergent Eastern Arabic numerals (٠١٢٣٤٥٦٧٨٩), which are what most Arabs use today. When you read about how Fibonacci promoted the use of Arabic numerals, adapted from the Arabs, it's easy to think that he must have been looking at "٠١٢٣٤٥٦٧٨٩", and that either he or some European copying his manuscript adapted these to the the "12345" forms you see in https://upload.wikimedia.org/wikipedia/commons/0/04/Liber_abbaci_magliab_f124r.jpg https://upload.wikimedia.org/wikipedia/commons/0/04/Liber_ab.... But if you look at https://en.wikipedia.org/wiki/File:The_Brahmi_numeral_system_and_its_descendants.png https://en.wikipedia.org/wiki/File:The_Brahmi_numeral_system... you can see that he would have had to coincidentally adapt them back to more nearly resemble the forms in the inscription in Chaturbhuj Temple at Gwalior from three centuries earlier.
  - jhgb 5y ago
    > All the Europeans did with them was to rotate the "4" by 90° To be honest, from the second picture you've linked, it would seem that North Africans didn't do almost anything with at least 0, 1, 2, 3, 7, 9 either. So what Dürer printed in the 1500s has 0, 1, 2, 3, 7, 9 from the Indians, 6, 8 from the West Africans, and 4 and 5 seem to be European developments. I have no idea how you get European "4" from the Ghobar numerals by rotating the respective Ghobar numeral. In fact topologically European "4" is more similar to the earlier Gwalior numeral, and the early European "4" in your picture is the Gwalior "4" upside down. > he would have had to coincidentally adapt them back to more nearly resemble the forms in the inscription in Chaturbhuj Temple at Gwalior from three centuries earlier ...but why are you contradicting yourself now? First you say that numeral shapes used in Europe were developed by North Africans and then you say that the forms come actually from India. Which one is it, then?
    - kragen 5y ago
      To me, the North African (Western Arabic) forms look intermediate between those from the Gwalior temple and those used by Fibonacci. The Eastern Arabic forms don't. Fibonacci traveled back and forth to Algeria with his father in his childhood, where he studied mathematics. Although he credited the Indians with the method of calculating with place-value numerals, he never traveled to India, but he traveled extensively to North Africa.

mc32 5y ago

The numerals are "Indo-Arabic". Arabs were a conduit but the number system was invented in the Indian subcontinent by Indian mathematicians, this was then adopted, centuries later, by Arab mathematicians who in turn exported/exposed it to the West.

lmilcin 5y ago
It is arabic numerals (https://en.wikipedia.org/wiki/Arabic_numerals https://en.wikipedia.org/wiki/Arabic_numerals). "Although the Hindu–Arabic numeral system[1][2] (i.e. decimal) was developed by Indian mathematicians around AD 500,[3] quite different forms for the digits were used initially. They were modified into Arabic numerals later in North Africa. " Arabic numerals does not only describe the concept of decimal system, but also the shape of digits. Hence "arabic numerals" is the correct description, and "Hindu-Arabic numerals" describes different numerals -- shapes for digits.
- mc32 5y ago
  Fair enough. The numeral system is Hindu and the typography is derived from Arabic thus Arabic, although what we use in most of the rest of the world diverges quite a bit from truly Arabic typographs. One could argue 0, 1, 2, 3, 9 are similar with some rotation , but 4, 5, 6, 7, and 8 do not look like Arabic numbers. Curiously there is overlap of some E. Arabic numerals and Brahmi numerals.
- jhgb 5y ago
  I'd definitely go with Chrisomalis on this one and just call them "Western numerals" to distinguish them from both Western Arabic and Eastern Arabic numerals. As you say, it's about the different shapes, and the three are definitely not the same.
kragen 5y ago
The numbering system was invented in India, but the particular numerals used for it in Europe (012345689) were invented by Arabs in North Africa. All the Europeans did with them was to rotate the "4" by 90°. This is easy to get confused about because of the subsequent conquest of North Africa by Europeans and the divergent Eastern Arabic numerals (٠١٢٣٤٥٦٧٨٩), which are what most Arabs use today. When you read about how Fibonacci promoted the use of Arabic numerals, adapted from the Arabs, it's easy to think that he must have been looking at "٠١٢٣٤٥٦٧٨٩", and that either he or some European copying his manuscript adapted these to the the "12345" forms you see in https://upload.wikimedia.org/wikipedia/commons/0/04/Liber_abbaci_magliab_f124r.jpg https://upload.wikimedia.org/wikipedia/commons/0/04/Liber_ab.... But if you look at https://en.wikipedia.org/wiki/File:The_Brahmi_numeral_system_and_its_descendants.png https://en.wikipedia.org/wiki/File:The_Brahmi_numeral_system... you can see that he would have had to coincidentally adapt them back to more nearly resemble the forms in the inscription in Chaturbhuj Temple at Gwalior from three centuries earlier.
- jhgb 5y ago
  > All the Europeans did with them was to rotate the "4" by 90° To be honest, from the second picture you've linked, it would seem that North Africans didn't do almost anything with at least 0, 1, 2, 3, 7, 9 either. So what Dürer printed in the 1500s has 0, 1, 2, 3, 7, 9 from the Indians, 6, 8 from the West Africans, and 4 and 5 seem to be European developments. I have no idea how you get European "4" from the Ghobar numerals by rotating the respective Ghobar numeral. In fact topologically European "4" is more similar to the earlier Gwalior numeral, and the early European "4" in your picture is the Gwalior "4" upside down. > he would have had to coincidentally adapt them back to more nearly resemble the forms in the inscription in Chaturbhuj Temple at Gwalior from three centuries earlier ...but why are you contradicting yourself now? First you say that numeral shapes used in Europe were developed by North Africans and then you say that the forms come actually from India. Which one is it, then?
  - kragen 5y ago
    To me, the North African (Western Arabic) forms look intermediate between those from the Gwalior temple and those used by Fibonacci. The Eastern Arabic forms don't. Fibonacci traveled back and forth to Algeria with his father in his childhood, where he studied mathematics. Although he credited the Indians with the method of calculating with place-value numerals, he never traveled to India, but he traveled extensively to North Africa.