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| quote: | | 1. Nr. 36 ist noch frei, war mal jp´s, aber er hat ja nu die 0 |
| quote: | Q: Is zero a number?
A: Yes, zero is a number but you are not alone if you wonder why. Indian mathematicians first came up with the number idea around 650 AD. Originally, perhaps as early as 200 AD, they used zero as a placeholder in another number. For example, in our notation: 216 is a different number than 2016. This use of zero advanced trade, commerce, and bookkeeping but does not qualify zero as a number. Zero, in its place-keeping function, is a kind of punctuation mark to help us interpret numbers correctly.
In about 630 AD, the great Indian mathematician, Brahmagupta, wrote the rules for arithmetic involving zero and negative numbers. This masterpiece brings zero into the realm of numbers. Zero is a count of nothing.
By the way, although Brahmagupta devised good rules for addition and subtraction, his rule for division by zero fails (e.g., 0/0 = 0). Not until 1828, did a German, Martin Ohm, successfully handle this problem: simply by outlawing division by zero. It is forbidden; else one obtains untrue results using other rules of arithmetic.
Zero advances human insight into numbers. The idea of numbers, basically, is the notion of counting. Three pebbles stand for three sheep. The number three is an abstraction from all collections containing three actual things.
Zero is a step farther into the abstract. Until then, each number stood for a count of something concrete. Zero, however, is a count of the elements in the completely empty set: nothing.
"...the word 'number' (in various languages and at various times) has had different meanings," says Andrew Gleason, mathematics professor emeritus at Harvard.
In classic Greek times it meant an integer at least three. Now it includes negative numbers (-1, -2...) and more.
People argue whether -1 or -2 is a number because you can't have -2 sheep. "This argument ... is pointless," says Gleason, "because it's a matter of definition... On the other hand, it seems that there is a super-convention that restricts the word 'number' to entities which have some sort of arithmetic. Thus, if you have two numbers ... you would expect that it would be meaningful to add them."
Telephone numbers, aren't really numbers, he says, because adding them has no meaning. Zero is a number, by definition and the rules of arithmetic. Add zero to any number and you obtain that number. |
| quote: | | Zero is a count of nothing |
Last edited by jp on Jul-28-2003 at 20:56
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