When you have tritanomaly, blue often looks green. You observe enough raised eyebrows and you lose confidence in your ability to tell the difference. You begin consulting a non-afflicted expert when the difference matters, like picking out shoes to match your shirt. But if you see blue and I see green, who is correct? Well, since only one in 10,000 of us is a tritanope, correctness always resides with the majority – the non-afflicted.
Does it matter what we label colors? I don’t think so, generally. But on this one day of the year, if you are of Irish descent, getting it right matters.