Comment by mci

Good luck living in a world without stable orbits and without a cross product. Stable orbits only exist in 3 dimensions [1]. Cross product only exists in 3 and 7 dimensions [2] thanks to quaternions and octonions.

[1]: https://en.wikipedia.org/wiki/Bertrand%27s_theorem

[2]: https://en.wikipedia.org/wiki/Seven-dimensional_cross_produc...