8 replies to this topic

[flamebirde]

There are 4 cardinal directions. East, West, North, and South. However, if you think about it, there is really only 2 true directions. Here is my reasoning.

If you go as far north as you can, then you will eventually hit the North Pole. You can't go any further north than the North pole, because any way you go from there is South. Same with going to the South pole.

However, it is not the same for East and West. You can go as far East as you want. There is no East Pole or something like that. Also the same for West. no matter how far East you go, you will nevr suddenly find yourself going West. So we come to this dillemma: there must be at least 2 subdivisions of directions. So..... which pair is the "true" piar of directions? Please tell me if my reasoning is flawed.

[MikeD]

Well East and West are not really direction. Since South and North are based on the magnetic fields of the earth. West is just left when facing North. If you go to the North pole you can't go in any other direction but for South.

[flamebirde]

so, there is really only North and South?

[Molly Mae]

I would say that's more of a side effect of the mechanism humans have used when defining the globe.

They are all four directions. North and south are directions relative to two particular points (the north pole and the south pole). East and west are directions relative to the point you are presently occupying (or alternately are directions relative to north and south, as Mike pointed out above).

[curr3nt]

A defination I found...

cardinal direction noun - A direction toward or away from either planetary rotation or the planetary poles. Bionian planets only have east and west; trionian planets additionally have north and south; tetronian planets have two more, marp and garp.

Distance towards marp or garp is measured in laptitude.

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I was also imagining a directional system based upon your position to the sun in the sky. East and west would be sunward and counter-sunward depending on the time of day. North/South would be right of sunward or left of sunward.

The time of day would have to be considered whenever directions were given. Also you would run into trouble giving directions if the longitude differed too much. Sunward morning in Japan would be closer to counter-sunward morning in New York.

No travel would be allowed between late dusk and early dawn.

I think it would break as soon as maps were invented.

[flamebirde]

wait... marp and garp? and is North right when facing West or is West right facing North?

[Molly Mae]

wait... marp and garp? and is North right when facing West or is West right facing North?

Marp and garp are cardinal directions in the fourth dimension, according to that link.

[Yoruichi-san]

I would say there are an infinite number of "directions", and they are a matter of perspective, i.e. frame of reference. Let's say I'm holding a compass perfectly flat and I designate the line along which it's pointing (magnetic north) as the y-axis. I call the direction "North", in unit vector form, <0,1,0>. I call the opposite direction, "South" <0,-1,0>, I call "West" <-1,0,0>, "East" <1,0,0>. I call the direction of the ground, "down" <0,0-1>, "up" <0,0,1>. Then there are an infinite number of "directions", vectors that are linear combinations of these, i.e <sqrt(2)/2,sqrt(2)/2,0> or "northeast", etc.

Obviously people on different parts of the planet has a different definition of "up" and "down". North, South, East, and West people use Earth's magnetic fields to "standardize", so they are the same for everyone in Earth's frame of reference. However, since the Earth is rotating, from the frame of reference of a different body of the universe (like another planet) they are constantly changing, i.e. what we call "North" will be pointing at Mars at some time, and at a different time will be pointing orthogonal, and at a different time will be pointing away.

[Quag]

There are 2 north and 2 south poles, The magnetic and the true poles. They are not in the same place, the magnetic moves around a bit too. Thus if you are at the North Pole you can head east or west as long as you base it on the use of the other pole. As an example from where I am currently The magnetic declination is 16 degrees west.
All this to say that If I am standing at the North Pole I can head east or west, and head to the other North pole though when you get near the poles compasses tend to get wonky so a GPS would help you out
BTW the magnetic NP is in Canada we rule!