How do I know the colors I see are the same colors you see?

I do not have a scientific answer to this, but i am presuming one way to approach this question is to also understand how colorblind tests would actually work for the majority of the population. If they didn't, that would mean that the colors don't interact with each other, such as the specific colors they use for those tests. All in all, since colorblind tests do work, I do believe that majority of us do see the world same way, in the same colors.