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Where and When Did the Symbols "+" and "–" Originate?

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Re: Where and When Did the Symbols "+" and "–" Originate?

#2
This always amazed me: "A Jewish tradition that dates from at least the 19th century is to write plus using a symbol like an inverted T. This practice was adopted into Israeli schools (this practice goes back to at least the 1940s)[11] and is still commonplace today in elementary schools (including secular schools) but in fewer secondary schools.[12] It is also used occasionally in books by religious authors, but most books for adults use the international symbol "+". The usual explanation for this practice is that it avoids the writing of a symbol "+" that looks like a Christian cross.[12]" [1]

[1] http://en.wikipedia.org/wiki/Plus_and_minus_signs#Alternativ...

Re: Where and When Did the Symbols "+" and "–" Originate?

#3

This always amazed me: "A Jewish tradition that dates from at least the 19th century is to write plus using a symbol like an inverted T. This practice was adopted into Israeli schools (this practice goes back to at least the 1940s)[11] and is still commonplace today in elementary schools (including secular schools) but in fewer secondary schools.[12] It is also used occasionally in books by religious authors, but mos…

And the symbol for the 4 cardinal directions (like on a map) gets written as: ⊕ (A circled plus.)

Re: Where and When Did the Symbols "+" and "–" Originate?

#4
I always thought the plus sign had to do with two entities meeting or being placed on top each other, like a road crossing or a pair of sticks, and that the minus sign was just a spinn-off of that sign and also made sense in the same way that Descartes used "..." according to the article.

Re: Where and When Did the Symbols "+" and "–" Originate?

#5
What fascinates me most about this story is how it illustrates what a young race we humans are intellectually.

If we ever want to be anything more than warring tribes, we must learn to accumulate knowledge together. Universal symbols for addition and substraction are the first small step on that very long road, yet it's only been a few hundred years since we took that step.

On the scale of the universe, we are like a baby who just minutes ago learned to grab onto objects and already is hell-bent on pouring a hot pot of tea on herself using this new capability.

Re: Where and When Did the Symbols "+" and "–" Originate?

#8
post #5

What fascinates me most about this story is how it illustrates what a young race we humans are intellectually. If we ever want to be anything more than warring tribes, we must learn to accumulate knowledge together. Universal symbols for addition and substraction are the first small step on that very long road, yet it's only been a few hundred years since we took that step. On the scale of the universe, we are like a…

On the scale of the universe we're virtually non-existent :)

Re: Where and When Did the Symbols "+" and "–" Originate?

#9

Several earliest known uses of other mathematical notations can be found at: http://jeff560.tripod.com/mathsym.html

> The asterisk was used by Johann Rahn (1622-1676) in 1659 in Teutsche Algebra

Interesting. I've always thought that the use of an asterisk to denote multiplication was some sort of compromise owing to the lack of a "×" key on a typical computer keyboard. But it seems that there are much older precedents for it.

Meanwhile, using a slash to denote division is explained in the Fractions page.

> The diagonal fraction bar (also called a solidus or virgule) was introduced because the horizontal fraction bar was difficult typographically, requiring three terraces of type. An early handwritten document with forward slashes in lieu of fraction bars is Thomas Twining's Ledger of 1718 ...

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