There is an existence proof "for some value of objective": Your and my own subjective tastes are also an objective determinant. With enough data from people, on

There is an existence proof "for some value of objective": Your and my own subjective tastes are also an objective determinant. With enough data from people, one might find some function over the domain of colour that yields pleasing combinations. I'd suggest you put your candidates up on http://www.colourlovers.com/ http://www.colourlovers.com/ and have them vote.