Relative Direction
The most common relative directions are left, right, forward(s), backward(s), up, and down. No absolute direction corresponds to any of the relative directions. This is a consequence of the translational invariance of the laws of physics: nature, loosely speaking, behaves the same no matter what direction one moves. As demonstrated by the Michelson-Morley null result, there is no absolute inertial frame of reference. There are definite relationships between the relative directions, however. Left and right, forward and backward, and up and down are three pairs of complementary directions, each pair orthogonal to both of the others. Relative directions are also known as egocentric coordinates.
Read more about Relative Direction: Traditions and Conventions, Geometry of Natural Environment, Nautical Terminology, Cultures Not Using Relative Directions, Left-right Confusion
Famous quotes containing the words relative and/or direction:
“Man may have his opinion as to the relative importance of feeding his body and nourishing his soul, but he is allowed by Nature to have no opinion whatever as to the need for feeding the body before the soul can think of anything but the body’s hunger.”
—George Bernard Shaw (1856–1950)
“The young ... look into visages dull-eyed, long-toothed, wattle-necked, and chop-fallen, something they have never been and which they cannot imagine ever being.... If it occurs to a young person, looking at us, that this is the direction in which he himself travels, how can he forgive, let alone bear the sight of, us, who constantly bring him the bad news of our own faces, bitter signposts pointing to his own destination?”
—Jessamyn West (1902–1984)