Both purple and green are secondary colours, and often associated with villains in comic books. This villainy is natural for both when they are juxtaposed because while they are tonally similar, they are very much at odds. Both refuse to concede to the other, and both attempt to be dominant when juxtaposed. Both have a cool element, from their common blue, and both also have a certain warmth, which green gets from yellow and purple gets from red. Certainly, from this perspective, purple wins, since red will beat yellow in almost any battle, but somehow green puts up a hell of a fight when battling it out with purple.
Category: Colour Theory
Studies in colour for the purpose of defining a personal style
Blue defers to Purple
Blue is business casual. Always a safe bet, blue can be worn with anything, because it can be interpreted as a neutral in almost any shade except perhaps the most vibrant of jewel tones. Purple, on the other hand, is very particular. It is lush and opulent. Decisive and daring. Paring a bright purple with a toned-down blue allows the purple to shine, and take its place in the spotlight, just as it deserves. Of course, the opposite works as well. A pastel violet will work very nicely with a bold cobalt, lending a sweetness to something vivid, yet even in this context, the violet will be dominant, because purple is so very powerful, and blue so very accommodating.
Orange and Blue are a safe risk
Orange is the colour of autumn, and of the 1970s, so even though an autumnal palette simultaneously evokes warmth and the cozy crispness of fall, it can also cause traumatic flashbacks to shag carpeting, brutalist architecture, and questionable fashions.
Blue is similarly contradictory. It is well loved, and ubiquitous in both fashion and administrative work, but this popularity is exactly what makes it so basic, so safe, so essentially neutral.
It is these dichotomies that make the pairing of orange and blue so daring. Orange is one of the most controversial colours (only yellow is more difficult to pull off), and blue is the most agreeable. Together they allow for rather low-risk experimentation.