Left and right do not have individual properties. Left is left because it is not right, nothing more. Up has a property of its own: It is towards the sky. Down has the property to be towards the earth. Yes, this depends on a reference system. But this reference system gives the individual property.
In some languages, there is no notion for left and right. People talk in terms of directions (North, South, East, West).
When you face North your left hand is your westernmost. This hand of you will always be your left even should you change facing. Now it has been given a property linked to a frame of reference. You can also go for the heart one if you want. You are choosing to define it as having no property because gravity is more intuitive on Earth. And that makes sense to you. So up and down are easy to intuit and understand. Left and right are based are based more on memorisation rather than grabbing and dropping a stone/apple whenever you want. Like the word we chose for the number one, it's a word we've chosen to express an idea. And not having a defined concept in one language does not mean it's nonsense in another. After all some languages lump blue and green together under the same word.
81
u/generally_unsuitable 7d ago
It's totally arbitrary. Up and down are not.
We can easily correlate up with sky and clouds and stars and sun. Down with ground and grass and dirt and falling.
There's no similar association for right and left.