In a rainbow the colors order is red then orange (made from red and yellow, thus making sense that it appears in between them) the yellow followed by green after which comes blue (again green formed from yellow and blue). The final color is purple, which is next to the blue' but not in any contact with the red.
The question is - is there any actual connection between the colors and there source as known to as (such as orange from yellow and red, the last two being the source) to its appearance in a rainbow? If so, why doesn't the purple follow the same logic? How is the purple seen were it is seen in a rainbow (where there is no red nearby)?