Define left/right

[AndrewAPrice]

Can somebody find the best definition for the directions 'left' or 'right'?

[Brynet-Inc]

<--

-->

?

[AJ]

Up and Down rotated by 90 degrees? What's the prize?

[AndrewAPrice]

Up and Down rotated by 90 degrees? What's the prize?

In which direction? Saying clockwise/counter-clockwise is cheating because you'd have to define which way a clock ticks.

[AJ]

Damn - knew I'd missed something! Still, I don't think Brynet wins either - he needs to define how arrows work

[Brynet-Inc]

Damn - knew I'd missed something! Still, I don't think Brynet wins either - he needs to define how arrows work

awww..

[Candy]

right: when viewing a human from the front, the side on which his heart lies
left: not right

[urxae]

right: when viewing a human from the front, the side on which his heart lies
left: not right

IIRC there is at least one medical "condition"[1] where the internal organs are mirrored with respect to the normal positioning. At least, that's what several hospital TV shows have told me...
I think it's pretty rare though, so perhaps something along the lines of "(in the majority of cases)" could be appended to fix that.
Your definition of "left" should probably be more along the lines of "the exact opposite direction of left", as your definition would also hold for directions like up, down, front and back, as well as every non-orthogonal direction except the exact opposite of right (and even anything that isn't a direction at all ).
Also, that definition of right seems to assume you already know you're only trying to tell left from right, as otherwise the answer would come out more like the correct answer to "up and slightly to the right", in relation to the center of gravity (the easiest-to-define "center" of the body I can think of)


[1]: Is that the correct term for something that is, AFAIK, completely harmless? (except perhaps for any damage caused by confused doctors before they figure it out )

[Candy]

right: when viewing a human from the front, the side on which his heart lies
left: not right

IIRC there is at least one medical "condition"[1] where the internal organs are mirrored with respect to the normal positioning. At least, that's what several hospital TV shows have told me...

Yep. Forgot about that one for a second. You could use for instance Lorentz' law in the explanation, but it would still require knowledge of the law.

Also a possibly nice explanation is the "odd page of the book" is right, the "even page of the book" is left. Some people making books didn't get the theory behind it so it's possible to get it wrong.

Your definition of "left" should probably be more along the lines of "the exact opposite direction of left", as your definition would also hold for directions like up, down, front and back, as well as every non-orthogonal direction except the exact opposite of right (and even anything that isn't a direction at all ).

Of course, that was a mathematical negation of the concept of right, like an inverted vector. You're right though . Just felt that defining them as booleans would be recognised (false=0; true=not false)

Also, that definition of right seems to assume you already know you're only trying to tell left from right, as otherwise the answer would come out more like the correct answer to "up and slightly to the right", in relation to the center of gravity (the easiest-to-define "center" of the body I can think of)

Yep.

[1]: Is that the correct term for something that is, AFAIK, completely harmless? (except perhaps for any damage caused by confused doctors before they figure it out )

It does increase the chance for failed surgery a bit, but ignoring surgical stuff it's entirely harmless. I wouldn't call it a condition though, that's sometimes used for illness. I think I'd choose "medical rarity" or "pathological difference" indicating it's associated with medicine and that it's both not common and harmless. Of course, I might be more wrong than you

[~]

"Left" is where you started writing C and "Right" where you ended writing a dot.


Other, make a cross of arrows:

Code: Select all

       ^
       |
       |
       |
<------------->
       |
       |
       |
       V

Call the horizontal arrow of this cross's section "Left":

Code: Select all

       ^
       |
       |
       |
<------

And call the horizontal arrow of this other cross's section "Right":

Code: Select all

       ^
       |
       |
       |
       ------->

Now the arrows are named (according to where goes the sharp part of the arrow):


Up:

Code: Select all

       ^
       |
       |
       |

Down:

Code: Select all

       |
       |
       |
       V

Left:

Code: Select all

<------

Right:

Code: Select all

------>

[Solar]

This assumes someone knows what "horizontal" is...

I'd try this approach: The majority of people (>80%) use a certain hand for doing things, like holding or throwing something. This is their right hand.

(You'd then have to make clear that it means right from their point of view.)

Just about everything else is depending on culture (arab is written right-to-left, several asian languages are written top-down) or assuming other knowledge to a point where that person shouldn't need having left and right explained to him.

Now, if that person hasn't seen many other humans in his / her life, or chanced to grow up in a community with a strong left-handed subgroup. But we are talking really pathologic cases here...

[os64dev]

if you put your hands flat on the table in front of you and spread your fingers: left is where your thumb points to the right and right is where your thumb points to the left. i hope this clarifies everything

[Combuster]

how about: if you look at the top of your hands, the left one is the one where the fingers form the letter L

[AndrewAPrice]

Just about everything else is depending on culture (arab is written right-to-left, several asian languages are written top-down) or assuming other knowledge to a point where that person shouldn't need having left and right explained to him.

How do we know left is not right, and right is not left, and our brain horizontally flips the image? After hundreds of thousands of years of no contact between the western/middle/eastern worlds, Middle-Eastern/Asian brains might have developed differently so that their perception of the world isn't flipped, therefore Arab could be a left-to-right language from their POV.

[~]

There are many things that can be best (re-)understood by disregarding the artificial name we have given to it.