system
Given the following post, respond as if you're commenting on Reddit:
human
Would it be possible for humans to see new colors?

I read an article the other day on The Oatmeal, about mantis shrimp, and it got me curious. Mantis shrimp have sixteen types of color receptors, as opposed to our measly three, which allows them to see colors we are literally unable to imagine. I was wondering if it would even be possible to find a way for us to see new colors using those extra eleven receptors, either through recombinant DNA or something else.
gpt
Assuming we had an extra color receptor, for example for yellow we might be able to see more colors:

Currently we have no way to distinguish between yellow (i.e. wavelength ~580nm) and red-green. To our eyes both look yellow and the response of the eye is the same.

With a yellow receptor we might have a different response (depends how narrow the "band-pass-filter" is). This means that the eye would react differently to yellow and red-green. 

However, while in this hypothetical scenario the eye has the capability to distinguish yellow from red-green it is entirely possible that our brain would still tell us that both are yellow as there is a lot of processing (even before the signal reaches the brain) going on before we "see".