There cannot be complex meanings for this concept, it is just a simple ‘a’ or a simple ‘b’ or a simple ‘c’. It can even be one colour. Imagine that you are looking at the sky, the simplest image: a blue background with different contours and shadows. Simplicity should be described as:
-the contour of a figure
-the human naked, without nothing else than its single presence…
Sense, sensibility, sentiment, sincerity, smile, stars, style, sunshine, surprise, sweet.
The quality or condition or being easy to understand or do. The quality or condition of being plain and natural. (1)
(1) Definition taken from: http://oxforddictionaries.com/ (4 September, 2011)