| Now your eye is pointing forward again, in the same direction as it was when
it started. But notice where the + is now compared to where it was at first.
Compared to before, the eye is on its side. It has violated Donders' law
If you try the same three rotations again the eye will end up upside down in the
head. This is can be painful!
Grant it, these are big rotations and normally the eye cannot turn by much more
than 45 deg. from center
But since the eye makes saccades a few times each second, a bad choice of
axis can quickly lead to this problem even the saccades are small.
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