The Etymology of Spectrometry

It's life or death. You're looking down at a mess of wires connected in varying combinations to a sturdy looking array of explosives. A red LED clock ticks the seconds down. 10, 9... In your hands is a pair of wire cutters. The radio stutters to life, "Cut the blue wire!" your temperamental commander shouts. You remember your dead partner and realise that after the events of the last two days, death would be a welcome change. You reach out and cut the wire. The universe skips a heartbeat before the clock flickers and dies. You saved the city, Seargeant, or should I say Captain. Unless you happen to be Welsh, that is.
In Welsh, as in a number of other languages, the word for blue encompasses green. Does this mean that, because they lack a mental label, they are unable to distinguish between the two colours? Colours are just words which have been invented to describe different sections of the visible electromagnetic spectrum from short-wavelength violet light to long wavelength red light. In this article from the Economist, two viewpoints among psychologists are identified. One states that human brains are hardwired to recognise and separate the 6 basic colours you might find in a cheap children's painting set. The other states that the spectrum is arbitrarily chopped up into segments based on social and linguistic factors. As always with these kinds of nature-nurture debates the answer probably lies somewhere in the middle; my personal bias tends towards the latter. Another recurring feature of these kinds of debates is that anyone can weigh in and sound like an expert, which makes it something ideal to save up for your next dinner party or night at home alone with your thoughts and a bottle of red. Or is that yellow?