Originally posted by twhitehead
Can black be seen? If you look up at the sky at night, do you not see the blackness of space?
Black is a color; one sees a black cat or a black car because some light is being reflected from the surface of the object which is darker/dimmer, or radiating at a different degree Kelvin, than other light-reflecting objects in the vicinity.
What do you see in a cave with no light at all? In the total absence of light, there is no seeing, so there is no color either.
What you see when you look up at the sky at night is a black expanse spangled with stars. What you see in the night sky are all the
places where stars aren't
by comparison with the points of light you do see. If there were no stars or other light-reflecting-refracting-bending celestial objects up there, people would not think they were looking at any anything fundamentally different than the inside of a cave. It would be the same, subjectively for humans, if the sky were one single gigantic mono-chromatic luminous expanse from horizon to horizon (we might imagine that the sky on Venus looks like this).
We call the dark expanse in between the stars "(outer) space" (which is to say interstellar void) but one is still liable to confuse "place" with "space." Outer space just happens to be a
very big place.
Place is equivalent to location or position, which is always relative to some other place/location/position, or relative to some visible object (such as a star or the walls of a fridge or our Earth when looking at the night sky), or with reference to some system of coordinates (such as latitude and longitude: e.g., a place in the Pacific Ocean). A place can be empty--which is what interstellar space mostly is (empty) and what would contain another jar of jelly in a fridge if no other solid is in that place.
Space is the logical presupposition of there being any place at all. One might think of it as the 'habitat'
wherein all places and all objects exist, as time is the
'whenin' all events and processes occur.
A place has dimensions (size), though they may be astronomically vast; space has no dimensions: it is the logical presupposition of dimensionality (at all).
Let me give you a metaphor: what you see when you look at a chess game is a board with 64 squares of alternating colors, two sets of figures (2 kings, 2 queens, 16 pawns, etc.), and the moves (e2-e4, c7-c6 etc.). You do not see that the king cannot be moved into check; no matter how many games you observe in which this move never occurs, you never see that it
cannot occur. The reason is that "the king cannot be moved into check" is not a move in the game or a figure in the game or a part of the board. It is a
rule of the game, not a
move within the game. Space is like that: it's one of the rules of the system, not one of the items within the system. We never see it, but we know it's there.
"What if light bends rather than reflecting? Surely an Einstein ring allows you to see the curvature of space. If you are seeing its curvature are you not seeing it?"
The fact that light can be bent (by gravitational lenses or whatever) shows that there is more than one rule of the game and that the rules form an interactive system, much as there is more than one rule of chess and they too form a system.
If you see an
instance of the application of a rule, are you seeing the
rule? That is the sort of question Wittgenstein might have racked his brain over. If I say "yes", just make sure you're not confusing the map for the territory!
I would say that one can be said to see space in the sense in which one can also be said to see the friendliness in a friend's smile, or to see that one is falling into a trap in chess. Falling into a trap is not an item on the board in the same way as the kings and queens; we interpret it into the position based on our understanding of the rules of the game. If you were to try to point to "falling into a trap", you could not point to anything
other than the kings and queens and the squares they were on.
One Simple Question
23 Nov '15 05:31
Back to Top