Wittgenstein on color, remark #7

Someone is given a certain yellow-green (or blue-green) and told to mix a less yellowish (or bluish) one — or told to pick it out from a number of color samples. A less yellowish green, however, is not a bluish one (and vice versa). and there is also such a task as choosing, or mixing a green that is neither yellowish nor bluish. I say "or mixing" because a green does not become both bluish [usual interpretation of 'grünlich', generally regarded as a slip of the pen] and yellowish because it is produced by a kind of mixture of yellow and blue.