Origin Story: ‘+’ and ‘-’ the basic signs of arithmetic

We can we never think of mathematics without the ‘+’ plus and ‘-’ minus signs. While we do have a plethora of mathematical symbols for division(÷), multiplication (×), integral (∫)etc, at its core its always the ‘+’ and ‘-’ symbols. From our elementary days, we’ve been taught about these two integral symbols. They could be considered as the ABCs’ of mathematics and things wouldn’t have been the same without them. The same symbols are used everywhere, around the world. A little curiosity to know how these originated and evolved to the present form wouldn’t hurt.

The signs as used in the earliest civilizations

The plus and minus signs (+ and −) are mathematical symbols used to represent operations of addition and subtraction as well as the notions of the positive and negative. Moreover, the Plus and Minus are Latin terms meaning “more” and “less”, respectively. The origins of these two symbols dates back to the Egyptian hieroglyphics where they used symbols which resembled ‘a pair of walking legs’, either walking away or towards, representing addition or subtraction. Similarly, just like the Greeks, the Hindus too, did not have a particular sign for addition and subtraction. Many a times, they used ‘yu’ to mark addition. ‘Yu’ was used in the Bakhshali manuscript arithmetic, belonging to the period of 3rd or 4th century. It was in the early 15th century Europe, it was noted that ‘P’ and ‘M’ were used for the same.

Early recorded history of the signs

It has been recorded that the sign ‘+’ has its origin from the Latin word ‘et’ which meant ‘and’. Nicole d’Oresme, astronomer and author of the book, ‘The Book of the Sky and the World’ in 14th century, used the ’+’ sign as a shorthand for the word ‘et’. The use of the ‘-’ sign was first recorded in the year 1481, from a manuscript of German algebra, located in Dresden Library. Johannes Widman, the famous German mathematician, published the first printed book named ‘Mercantile Arithmetic’ in Leipzig, 1489, where he used the ‘+’ and ‘-’ signs. The beginning of 17th Century also saw the usage of these two symbols by mathematicians Cavalieri and Gloriosi as well as astronomer Christopher Clavius.

But it was Robert Recorde, the acclaimed Welsh mathematician and designer of the equal (=) sign who introduced to Britain in 1557, the same Plus and Minus that we’ve been using till now. He described the two signs in the following words:

“There be other 2 signs in often use of which the first is made thus + and betokeneth more: the other is thus made — and betokeneth lesse.”

It seems there were different versions of these signs used by various people, but it was Robert Recorde who gave us the signs that we use till now, passed generations after generations before being accepted universally.

The first equation ever written, by Robert Recorde in his treatise The Whetstone of Witte, in 1557. The equation when represented in modern terms, “14x+15=71” by , and its solution is 4.

Did you know?

A Jewish tradition which dates back to the 19th century writes the plus symbol using something which resembles an inverted T and is being used even now in Jewish elementary schools. The explanation for which is that it avoids the usual ‘+’ symbol which looks awfully close to the Christian Cross.

Originally published at www.edtechboard.com on March 20, 2013.