Colour is something you do.

Light carries wavelengths. Colour is what an eye and a brain make of them, and our index makes its colours the same way.

1 · The walk · colour

In 1666 Isaac Newton let a beam of sunlight through a prism and watched it fan out into a band of colours. Years later he wrote one of the most careful sentences in science. The rays themselves, he said, are not coloured. They carry a power to stir up the sensation of a colour, and the colour happens in the one who sees.

Three centuries on, we know how. Your eye has three kinds of colour sensor, called cones. One answers most to short waves, one to medium and one to long. No single cone knows what colour it is looking at. Your brain compares their three answers, and the comparison is the colour.

Three answers, one colour

The eye’s three kinds of cone, each tuned to its own stretch of the spectrum. Pick a light.

Blue light: the short cones answer most, and the others less. Your brain says blue.

Each kind of cone answers to its own stretch of the spectrum. The colour you see is your brain comparing their three answers.

That is why magenta exists. Look for it in a rainbow and you won’t find it: no single wave of light is magenta. Red and blue arrive together with little green between them, the cones answer in a pattern no single wave could make, and your brain gives that pattern a colour of its own. Colour is something you do.

Made by looking

In the Observer’s Index, a concept’s colour is made the same way. Every concept your organisation works with starts dark. How light it grows is made by the looks your people and your AI hand back, and by nothing else. On the map, so is how vivid it reads. There is no dial to set and no colour to type in.

And as in the eye, what counts is how the looks compare. A concept glows when its looks agree and when the threads they raise are tied off, and it softens when they pull apart. How vivid it is answers to how its looks relate, the way the colours you see answer to how your cones compare.

So a colour in the index is a record of minds at work: made by seeing, and only by seeing.

For your organisation: every colour you read was made by your people and your AI looking, so the picture shows what your organisation has actually seen.

Where we’re heading

Many minds, each with its own view, and one picture made from how they compare: an organisation that sees the way an eye does.

See the Observer’s Index

What stands under this piece

Proved: a theorem in our own maths. Built in: how the index works. From the field: something observed, by scientists or in our own index. Likeness: a comparison, not a proof.

Built in: Every concept starts dark, and only the looks handed back about it can light it.
Proved: All else being equal, a look that settles a thread an earlier look left open makes the concept more vivid.
From the field: The eye has three kinds of cone, each most sensitive to its own stretch of the spectrum: short, medium and long waves.
Likeness: The eye’s three cones beside our index’s many looks: a likeness we enjoy. It is a picture, not a proof.