The difference between these two pictures demonstrates Magnus’s revised theory.
The picture on the top is what Europeans see, and the picture on the bottom is what Magnus argued the ancients would have seen: the red hues are just as vivid, but the cooler colors green and blue are much less so.
This lack ofvividness, he said, would account for their lack of interest in finding separate names for such colors, and it would also explain the reports from the respondents to his questionnaires, which frequently mentioned the greater hesitation among the natives in distinguishing the cooler colors for which they had no names.

Why does the egocentric system feel so much easier and more natu­ ral to handle? Simply because we always know where “in front of” us is and where “behind” and “left” and “right” are. We don’t need a map or a compass to work this out, we don’t need to look at the sun or the North Star, we just feel it, because the egocentric system of coordinates is based directly on our own body and our immediate visual field. The front-back axis cuts right between our two eyes: it is a long imaginary line that extends straight from our nose into the distance and which turns with our nose and eyes wherever and whenever they turn. And likewise, the left-right axis, which cuts through our shoulders, always obligingly adapts itself to our own orientation.
The system of geographic coordinates, on the other hand, is based on external concepts that do not adapt themselves to our own orienta­ tion and that need to be computed (or remembered) from the position ofthe sun or the stars or from features ofthe landscape. So on the whole, we revert to the geographic coordinates only when we really need to do so: if the egocentric system is not up for the task or if the geographic directions are specifically relevant (for instance, in evaluating the merits ofsouth-facing rooms).