trigonometric inequality
$ d(x, y) + d(y, z) \ge d(x, z)
Condition that the distance between x and z is less than or equal to "the sum of the distance between x and y and the distance between y and z".
That "going directly from x to z is a shorter distance than going after a detour to y."
It is valid with respect to physical distance.
There are often cases where it is not possible to establish a relationship between the words "distant and close" in terms of Metaphors of Distance. ---
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