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## Yes, Virginia124-25=179

Mathematicians are respected for their precision, yet I despise some of out symbolic creations.

An example is the expression 24-(-15) =... The problem is that one of the negative signs is an operation symbol and the other negative sign denotes the sign of a number.

Mathematicians should have done better and avoided such confusion... which only leads to the simplistic rule change of replace - - with +. Ugh!

The situation is complicated further by calculators, which have different keys for the different meanings of the symbol -. Ugh!

Now, the Egyptian hieroglyphic sign for addition looks like a pair of legs walking in one direction, with the reverse image of the legs indicating subtraction. Unfortunately, the Egyptians did not have negative numbers.

The Chinese world had multiple subtraction symbols, but used the colors red and black to denote positive numbers and negative numbers respectively...thus, no ambiguity.

Early German, Swiss, and Dutch books sometimes used the symbol ÷ for subtraction (now our division symbol). Some seventeenth century books (e.g., by Descartes or Mersenne) denoted subtraction by two dots "∙∙" or three dots "∙∙∙" and then avoided confusion with sign - representing negative numbers.

Some mathematics authors went so far as to use the four phases of the moon to represent the four operations, trying to avoid confusion.

But, consider this suggestion: We should convert to base -10, as then all positive and negative numbers need no sign. That is, the value or nature of the number is captured within the number itself.

For example, our numbers +15 and -15 would be represented in base -10 as 195 and 25 respectively. And, in base -10, the expression 24-(-15) =... becomes 124-25=179.

You don't believe me....start playing around with base -10 and enjoy its many merits!

Or, you can investigate how the great Leibniz actually experimented with the use of different symbols for operations. As to multiplication, he tried six different options: dot, cross, comma, semicolon, asterisk, and oddly enough, a cup!