Arc:)-en-c:)

When we see a rainbow, there are actually an infinity of nuances even if we only see six dominant colors
(red, orange, yellow, green, blue & purple) but there are so much more not visible by human eye.

Isaac Newton observed these six colors during his experiment of decomposition of light by a prism.

even if but he decided to add the indigo color to match the number of colors with the number seven.

This number has a special status in many cultures: 7 days of the week, 7 sins...