It was then that I remembered the colour blue, the blue of the sky in nice that was at the origin of my career as monochromist. I started work towards the end of 1956 and in 1957 I had an exhibition in Milan which consisted entirely of what I dared to call my 'Epoque bleue. Yves Klein
A very great vision is needed, and the man who has it must follow it as the eagle seeks the deepest blue of the sky. Crazy Horse
It was morning; through the high window I saw the pure, bright blue of the sky as it hovered cheerfully over the long roofs of the neighboring houses. It too seemed full of joy, as if it had special plans, and had put on its finest clothes for the occasion. Hermann Hesse
Look more often at the stars. When you have a weight on your soul, look at the stars or the blue of the sky. When you feel sad, when they offend you -- stop yourselves... with the heavens. Then your soul will find peace. Pavel Florensky