A Pinch of History–Decimal Notation Over Time

Transcript

A Pinch of History–Decimal Notation Over Time This section tells us that the way we write decimals today, using a point (.), wasn't invented overnight. It developed over many centuries and through the contributions of different cultures. Here's the timeline as described in the book: Ancient India (as early as the 8th century): The idea of using decimal fractions—that is, fractions with denominators like 10, 100, 1000, etc.—was already present in the works of ancient Indian mathematicians and astronomers. For example, the important mathematician Śhrīdharāchārya used these concepts in his works on arithmetic. The Arab World (around 950 CE): An Arab mathematician named Abū'l-Ḥasan al-Uqlīdisī wrote a book called The Book of Chapters on Indian Arithmetic. In this book, he described a system of decimal notation that was very close to what we use today. For example, to write the number 0.059375, he would have written it as 0059375 (with a vertical mark over the last digit of the whole number part, which is 0 in this case). 15th Century Developments: As the idea spread, people tried different ways to separate the whole number part from the fractional part. Some of the methods used were: Placing a vertical mark on the last digit of the whole number Using different colors for the whole and fractional parts. Writing a numerical superscript to show how many decimal places there were. For example, 0.36 might have been written as 36². 16th Century - The Point and Comma Emerge: John Napier (a Scottish mathematician) and Christopher Clavius (a German mathematician) started using the point (.) to separate the whole and fractional parts, which is the system most commonly used today. At the same time, François Viète (a French mathematician) used the comma (,) as the separator instead. The book concludes by mentioning that even today, the comma is still used as the decimal separator in many countries. However, the decimal point has become the most popular and enduring notation worldwide.