“Although there are almost innumerable shade of differences in the colour of wine, they are all variety of two, the reddish and the yellowish color. I say reddish, for we know no kind of wine that is actually red or yellow. What we call red in wine is violet, mixture of red and blue. We do not in chemistry speak of the reddish wine as red, but designate its hue by the term wine-colour.”
– from G.J. Mulder’s Chemistry of Wine, 1857, London. p198
Sometimes, generalization for the sake of simplicity is worthwhile. Inaccuracies on the scale of generalizations can make communication so much easier. Can you imagine how Mulder might have asked one of his chemist friends what sort of wine he would like with his roast chicken?