It is well known that in European languages people write from left to right, whereas in Arabic, Farsi, Hebrew, Urdu, and some other languages, writing and reading from right to left is accepted. It seems that this distinction is quite clear and it has a pure two-dimensional origin, due to the fact that writing is a “planar (two-dimensional) process.” However, close inspection immediately demonstrates that the situation is more complicated due to the fact that distinguishing between left and right rotations calls for three dimensions.

Unit vectors x and y do not form the right- (or left-) hand coordinate system until the direction of the vector z is fixed. The same is true for defining of our English writing and reading as occurring from left to right. In this case, we also have the three-dimensional problem, shown in Fig. 1. The triad of unit vectors is formed by the...

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