Problem:
If I would show someone a yellow object and ask them, "is this object yellow?" That person would say "yes".
But I could never know if my perception of the color yellow is the same as that other person's.
Because he or she could actually be seeing, what I know to be the color green.
But then tells me that its the color yellow because that has been taught to him or her from young age.
Question: So how can you test if people are really seeing the same color? Please give its description.