This is a good question and I believe that it is the phenomenon that philosphers and psychologists refer to as a qualia (or quale pl.). I believe you cannot be certain that anyone elses perceptions are identical to your own even if they might be similar. For me this defines an unchangable limit of science. We will never know.
THE UNITED KINGDOM / DEC 6, 2005 11:11 AM EST
blue is blue.
THE UNITED STATES / DEC 6, 2005 10:44 AM EST
it possible but it does not matter because its just a convention. we call it blue and it does not matter if we, in fact all see the same. at least i think so...
SWITZERLAND / DEC 6, 2005 10:43 AM EST
No. Somebody can be taught to call the sky red and tomatoes blue, but this person will consistently call blue objects red and red objects blue, so in fact he sees the same colors as you but gives them a different name.