Why Zero is neither Positive nor Negative
Date: 10/5/95 at 22:5:27 From: Anonymous Subject: Is 0 a negative or a positive? Dear Dr. Math, My class and I are wondering if 0 is a negative or a positive number and why. My name is David and I am in fifth grade at Kyrene De La Sierra in Phoenix. Sincerely, Ms. Kieselbach's class
Date: 10/6/95 at 16:16:32 From: Doctor Ken Subject: Re: Is 0 a negative or a positive? Hello! Actually, zero is neither a negative or a positive number. The whole idea of positive and negative is defined in terms of zero. Negative numbers are numbers that are smaller than zero, and positive numbers are numbers that are bigger than zero. Since zero isn't bigger or smaller than itself (just like you're not older than yourself, or taller than yourself), zero is neither positive nor negative. People sometimes talk about the "non-negative" numbers, and what that means is all the numbers that aren't negative, in other words all the positive numbers and zero. So the only difference between the set of positive numbers and the set of non-negative numbers is that zero isn't in the first set, but it is in the second. Similarly, the "non-positive" numbers are the negative numbers together with zero. -Doctor Ken, The Geometry Forum
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